A/N: lol can't believe I wrote a part 2 for this but it's a strange year. Anyway, I'm 95% sure if the show ever played with the core couplings, it would be a huge mess. The other 5% of me is thinking maybe the chaos would have been fun.

"What if Ryan can't forgive me?" Seth worries as they sit in the airport lounge together.

"He will, Seth. He'll understand," Marissa says, lightly squeezing his hand. Seth looks at her, a mixture of sadness and paranoia.

"But, what if?" he says again.

"Seth…" Marissa says warily. They have had this conversation and she is running out of ways to reassure him. Seth reads the slight annoyance in her voice.

"Sorry, God, I should really shut up," he says hastily.

"No, it's ok, Seth. It's just, I don't know what else to say."

"I know, I know, I'm just stressed," Seth says. "I don't want to lose Ryan," he adds quietly. Marissa looks at him softly and intertwines their hands.

"Seth, believe me when I say you matter just as much to Ryan as he does to you. He's not going to turn his back on you."

Seth's expression mellows. "Thanks," he whispers and leans in to kiss her.

A moment later he tells her, "Whatever happens, we have each other."

. . .

They have been dating for four months now, without telling any of their family. It was Marissa's idea to tell everyone when they went home for Christmukkah. They both knew it was for the best. Being in New York was a wonderful bubble. It was just them and their relationship. At some point, all bubbles need to burst.

When they arrive in Newport, Seth is on edge, ever conscious of having to tell Ryan. Marissa too worries about telling Summer. No matter what they tell each other, the guilt is all consuming.

. . .

"There's something I need to tell you," Seth says to Ryan in the poolhouse. Ryan gives him a puzzled look but waves his hand for him to continue.

Seth takes a deep breath.

"I'm seeing someone."

Ryan is bemused, failing to see the seriousness in this.

"That's great Seth."

Seth prays to Jesus and Moses.

"It's, well, you see, it's - I'm seeing Marissa."

Seth feels like he is on the verge of choking. He stares at Ryan, watching his blank expression, dying for every second that Ryan says nothing.

"Marissa?" Ryan repeats, confusion written all over his face. Seth nods.

"My Marissa?" Ryan erupts and Seth almost winces. He hates that. He wants to tell him that she isn't his anymore. It almost negates his desire to grovel for forgiveness. Almost.

"I'm sorry, man," he says dejected.

"How is that even possible?"

Seth shrugs nervously.

"We get on, you know. I don't know how to explain it, it just happened. I realised I liked her, she liked me and we work."

"How long?" Ryan asks instantly. His eyes are already brooding and he can see the Ryan Atwood defense mechanisms being over-wrought.

"Four months."

"How long have you liked her?"

"Does it matter?" he attempts, his reluctance saying everything unspoken.

"Yes," Ryan insists.

"Since Hawaii," Seth admits.

"Seriously? The whole time I was with her."

"There was never anything going on between us. She had no idea. I was not on her radar."

"She talked to you all the time."

"It was friendly. Never anything more, not when she was with you."

Ryan's impassive, staring back at him.

"Do you love her?" he questions.

The silence is deafening.

"Yeah," Seth admits and watches the trust break between them. "I'm so so sorry," he tries, "I wish it wasn't like this, but you have to understand, man. I never wanted to hurt you."

"I don't care, Seth," Ryan bluffs. "We broke up."

"But you do care, I can tell you're pissed off."

"What do you expect?" Ryan snaps. "Do you want my blessing?"

"No, well, maybe, I don't know," Seth stutters helplessly.

Ryan sighs, "I need some time, and space."

. . .

Seth calls Marissa and tells her that Ryan hates him. She soothes him, tries to convince him that Ryan will get over it. But Seth is belligerent in his pessimism.

She promises to talk to him and he tells her not to bother. Seth worries that if she does, he may lose her as well. He wonders who she would choose if Ryan wanted her back. How can he even compete?

Marissa tells him that she owes it to Ryan to also explain.

Seth spends the remainder of the night wallowing in his self-pity and insecurities.

. . .

Before Ryan, Marissa speaks to Summer. They go for lunch at a new place on the pier. It's the first time they have seen each other in person in a year and a half.

"Wow, Cohen, really?" Summer says when Marissa breaks the news.

"But you should know that this is 100% new. Like I never wanted him when you were with him. But this last year especially, we've just connected," Marissa rapidly explains. "Do you hate me?"

"No," Summer says quickly, surprising them both. "It's definitely strange, very strange and I think I will need some time to process but I don't hate you Coop."

"I'm sorry," Marissa says, even as she relaxes at Summer's assurance.

"I'll always care about him but I knew he would move on one day. I never imagined it would be with you."

"Are we, can we be okay? With time?" Marissa questions.

Summer flashes her a smile.

"You're my best friend forever, Coop. Cohen's not going to stand in the way of that."

Marissa's heart swells, realising then how heartbroken she would have been had Summer answered differently.

. . .

Chrismukkah lunch is tense and foreboding. The parents don't know yet but it is obvious to everyone that the once four friends are deeply on edge. Seth doesn't make his usual jokes. Ryan is quieter than normal. Marissa looks pensively from Seth to Ryan to Seth again. Summer thinks Christmas with her boyfriend's family, who hate her, might be better than this awkwardness.

"How's the new job going, Seth?" Kirsten asks.

"Good," Seth replies curtly. Kirsten waits for him to elaborate and when he adds nothing, she and Sandy share a look of confusion. Even Julie and Neil find it odd. Seth is never voluntarily so quiet.

"Marissa, I heard you got a new promotion," Sandy tries.

"I'm so proud of you, honey," Julie chimes in.

"Thanks. But it's temporary, I'm just filling in for my manager while she's on maternity leave," Marissa replies politely.

"She's being modest," Seth interjects. "She'll be Vogue's lifestyle editor in no time."

At Seth's contribution, Ryan's eyes shoot up, sharply glaring. Nobody misses it.

"I loved the piece on sustainable fashion in the last issue," Summer tries to break the tension.

"Let's just say somebody inspired me," Marissa sweetly tells her friend.

"Climate change is so important," Seth contributes idly, his fork pushing the roast potatoes on his plate around.

"Ryan actually has a new green partnership for his latest housing project," Kirsten adds

"That's cool, Atwood," Summer says.

"It's nothing," Ryan replies, shrugging. There's another awkward pause, and then Ryan's standing up and asking to be excused.

"I'm not feeling too great." he lamely lies. "Sorry, Kisten, the food's great but I need to get some air."

"Is everything okay?" Kirsten checks.

"Look-," Seth tries to interrupt.

"Not now Seth," Ryan snaps.

Without another word, everyone watches as he grabs his keys and walks out.

Julie looks to the whole group, a curious look of fascination on his face.

"What the hell just happened?"

Seth and Marissa share a worried glance. They know it's time.

. . .

"I don't want to talk," Ryan shouts when he sees Marissa approaching the lifeguard stand.

Ignoring him, she walks up the rampart.

"Will you please cut him some slack?"

"Why?"

"Because we did nothing wrong."

"Really, Marissa? Do you really think that?" Ryan shoots back, his anger visible.

"We were broken up. You broke up with me. "

Time and time again, she almost adds.

"I know you love to act like our relationship meant nothing to me. Or that it meant more to you than it did to me. Some bullshit like that," Ryan vents. "But you know, Seth knows, you mattered more than anyone else I've been with me."

"Ryan," Marissa says with a sigh.

"I fucking loved you and now you're fucking my best friend, my fucking brother. For all my mistakes, I would never do that to you."

Marissa hugs herself tighter, feeling guilty and embarrassed. She's taken aback at his flood of words.

"I'm sorry," she apologizes despairingly.

"Yeah, Seth's said that a few times."

"I honestly didn't think you would have cared this much," she tells him.

"Because I never loved you, right?" Ryan says sarcastically.

"No," Marissa shakes her head. "Because when we broke up this time, it felt final. You seemed ready to move on. And from what Seth had told me, it sounded like you had."

"I went on a few dates and was in a 3 month relationship. You call that moving on?"

"Jesus, Ryan, I don't know. It's not like you kept in touch. And I've never been great at reading your mind," Marissa snaps.

"The feeling's mutual," he bites back.

Marissa presses her fingers on her brow, breathing a sigh of frustration. Ryan leans against the lifeguard stand, arms folded defensively. When she dares a look at him, she can see that he's more hurt than he is angry.

"It feels like we are fighting about more than one thing right now," she tells him.

"Hasn't that always been us?"

"When I was with you, I didn't have these feelings for Seth."

"He did for you."

It's funny, she thinks, how all her fights with Ryan always came back to other guys being in love with her.

"I didn't."

"When did it change?"

"In New York," she admits.

"You just realised one day?" he questions, sounding defeated.

"Sort of, but not quite. We were friends. He became my best friend."

"I thought Summer was your best friend," Ryan challenges drily.

"She is. She always will be. But with Seth, it was different. He was present, embedded in my life. I don't mean to hurt you when I say this, but we work. We are functional."

"And we never were," Ryan completes for her.

Marissa shrugs. "Not never, but it was a minority rather than a majority. You said as much yourself."

"I always thought I would be fine when you moved on. I never banked on it being with Seth."

"Neither of us meant for this to happen. We're not so selfish or stupid to think that it isn't hurtful. Maybe we didn't realise how much."

Ryan's quiet at her words, his eyes downcast and averted away.

Marissa watches him closely, running a tired hand through her flowing hair. The wind's picking up.

"He'll choose you over me, you know. If it comes down to it."

Ryan shakes his head.

"I wouldn't be so sure," he tells her, but not unkindly.

"Just come home," she tries again. "Talk to him and give him a chance. This isn't worth ruining your relationship with him."

He is silent in response but when she walks away, she hears footsteps behind her.

. . .

They drive back in separate cars, both of them replaying the conversation in their minds.

Maybe this is worth ruining his relationship with Seth over, he momentarily thinks. But then, he's not sure what he wants either. Does he want them to break up? Instinctively, maybe, yes. Does he want Marissa back? Not really. He knows they don't work, he's made peace with that. Accepted that he can't be who she needs him to be, not entirely.

Deep down, he can admit he wants Seth to be happy. Marissa too.

So really, where does that leave him?

. . .

Seth's lying on the floor of his childhood bedroom, idly holding Captain Oats in his hand.

"I really screwed things up, Oats," he mumbles to his toy horse. He's about to enter into a wallowing monologue. Despite his bravado earlier when Marissa had suggested, or rather insisted, that she be the one to go speak to Ryan, he was on the precipice of a spiral.

Before the thought can go much further, there's a knock on his door.

"I don't want to talk, mom," he shouts from his floor.

Then the door opens, and it's Julie Cooper standing in his room.

He rushes to sit up, and make himself look more presentable. He really doesn't want his girlfriend's mom to think he speaks to inanimate objects.

"Seth," Julie greets.

"Hi, um, what are you doing here?"

Shit, he thinks. He had been so focused on Ryan's reaction, that he had forgotten that Marissa's mother was Julie fucking Cooper.

"So you and Marissa, huh?" she says nonchalantly.

"Yeah," he replies. "We are going steady, as they say. Boyfriend and girlfriend. But you know that, now, obviously."

"Seth," Julie stops his rambling. "I'm glad."

"You're glad? Like glad as in you approve of me?" he checks.

"I'll be honest, most of the time, I don't know what you're talking about. You're a little strange. But my daughter's been very happy this past year. I couldn't work out why, and you're obviously the reason."

Seth processes the information, setting aside the obvious insults and focussing on the positives.

"Thanks, I think."

"You should be. I never said this to Ryan."

"Do you think," he hesitates for a moment. He feels pathetic for asking his girlfriend's mother but he's running low on confidants at the moment. "She's over him, right?"

"Seth," Julie warns and rolls her eyes at him. "For what it's worth, Marissa doesn't tell me much about him. I think she's never considered me to be objective, but who knows, maybe there isn't much to say."

Seth scoffs, "I doubt that."

Not with all their heartache and drama.

"But the point is she's chosen to be with you. And you can't be afraid of Ryan. You need to be a man."

Seth nods in understanding.

"I can be a man," he repeats, and finds that he actually means it.

. . .

"We shouldn't walk in together," Ryan quietly tells Marissa when they're both parked in the Cohen driveway.

"Why?" Marissa asks, confused.

"It's not a good look. Seth will take it badly," Ryan tries to explain. He's seen enough of Seth's neurosis over Summer to know this.

Ryan sees the frown on her face, as she thinks it over.

"He knows I went to see you. It's silly trying to pretend otherwise," she insists.

"Fine," Ryan responds, belligerently. "Not my problem," he mumbles beneath his breath.

. .

When they walk into the house, they find the parents sitting in the lounge speaking in hushed tones. The topic of conversation is obvious.

Marissa clears her throat, making their presence known.

"Feeling better, kid?" Sandy asks, aiming for a semblance of normalcy.

"Yeah," Ryan replies. It's partially true.

"Where are Seth and Summer?" Marissa asks.

"Summer left about half an hour ago. Seth's in his room," Kirsten tells them.

Ryan and Marissa glance at each other.

"I'll speak to him later," he promises her weakly.

She nods, trusting his word, however lackluster it sounds, and hoping that they can all make it through this.

. . .

She finds him lying on his bed, pretending to read the latest Legion, but his mind is clearly adrift.

"Hey," she greets.

"Hey," he replies, an immediate grin coming across his face at seeing her. He scoots over on the bed, making room for her to lie next to him. She rests her head on his shoulder, enjoying the quiet before they get to the inevitable conversation.

"So, how did it go?"

"Not great, but not terrible either. He came home at least. And he said he would talk to you."

"He did?" Seth sounds surprised. "Must have been more good than bad then."

His insinuation is not lost on her.

"There's nothing between me and Ryan," she tells him.

"Not nothing," Seth corrects. "I'm not saying this to pick a fight but there will always be something there. Just like me and Summer."

Marissa turns to face him, sitting up straighter.

"Is there something you should be telling me?" she challenges.

"No, I don't mean it like that. You know what I mean. You'll always care about Ryan, I'll always care about Summer, and vice versa."

"What's your point Seth?"

Seth picks at a loose thread on his bedsheet. This conversation had taken a turn he hadn't planned for.

"Can this actually work between us?" he asks genuinely.

"I hope so," Marissa tells him.

"I don't want to lose you. But there's all this history between us, and Ryan, and I don't know how we even begin to move past it."

"Look, you're right, I can't tell you that I feel nothing for Ryan. But caring about him is very different to being in love with him. So you have to trust me when I tell you that I want you, and I love you."

Her admission means the world to him. He's grateful, he truly is.

But there's still this gaping anxiety within him.

Even if he has Marissa, what if he loses Ryan forever?

. . .

He sits in the lounge, watching a rerun of Home Alone. It's approaching midnight, but he can't sleep. His mind is still too distracted. Then on cue, he watches as Ryan enters.

There's silence and apathy at first. Ryan gets a dry bowl of cereal, and he thinks he'll retreat back to the poolhouse. Instead Ryan comes over, and sits on the adjacent couch.

"Can't sleep?" Ryan asks.

"No," Seth replies.

"Me neither," Ryan concurs with pursed lips.

It's a start, Seth thinks.

"You want to talk?" Seth tries again.

Ryan shrugs.

"What's there to say?"

"How about what you feel?"

Ryan snorts.

"Marissa used to say that to me," he says cynically.

"Well, she has a point."

"You want me to tell you it's ok. But it's not," Ryan responds bluntly.

"Why aren't you ok with us?"

"Because it's a fucking betrayal."

"Is it?" Seth presses quietly. "You and Marissa have been over for a long time, unless you still..."

"I'm not still pining for her, if that's what you're asking."

"Then what is it?"

"How would you feel if I hooked up with Summer?"

"If you hooked up with her right after she left me and I was still in love with her, then yeah, I would be fucking living. But right now, it would be strange and awkward, but I would be okay with it."

"Why didn't you guys tell me then? When you first started dating? Why wait? If there was really nothing wrong about it." Ryan challenges back.

"Because look how well this has gone." Seth throws his hands in the air, getting flustered. "Can you blame us for waiting? And we wanted to test the waters first. See if there was even something between us which is worth fighting for."

Ryan's still glaring at him but the harshness softens just a touch.

He sounds solemn when he asks, "So you decided it was worth it?"

Seth nods.

"I wouldn't be risking your friendship for anything less."

. . .

They both wake early at dawn, their paths colliding in the kitchen. Ryan prepares the coffee and wordlessly offers Seth a cup. Seth takes it with uncharacteristically little comment, saying only a brief thanks.

They sit side by side on the kitchen island, both in deep contemplation.

"I really am very sorry," Seth repeats.

This time, Ryan shakes his head.

"You've apologised enough," he says. He moves his spoon listlessly around his bowl of cereal.

"I always thought when Marissa moved on, like really fell in love with somebody else, I thought it would be so far removed from me, that it wouldn't matter. Then she chose you, my best friend. It's a lot to accept."

"I get that," Seth admits.

"But I don't want to be an obstacle," Ryan tells him. "It's still strange to think about. But if she makes you happy, then I won't stand in the way of that."

"She does," Seth says shyly, an apologetic smile on his face.

The revelation doesn't hurt Ryan quite so much as the first time.

. . .

"I can't wait to go home," Marissa tells him as they sit in the departure lounge. Their flight has been delayed by two hours.

"Mhmm, one week of Newport was more than enough," Seth muses.

"Are you happy with everything?" Marissa checks.

"I guess so. Ryan doesn't hate me, so I'll take it as a win."

"He loves you, Seth."

"Probably closer to a tepid like at the moment. But we can work with that," he comments, making her laugh.

"It feels a little odd that everyone knows."

"Good or bad?"

"Good," Marissa affirms. "It makes everything more real."

Seth grins at her, holds her hand in his.

"Look about before, I know I was freaking out about you and Ryan, and doubting you when I shouldn't have been."

"It's fine given everything going on," Marissa shrugs off.

"I should have trusted you. And I want you to know that I do trust you. Completely."

"And I trust you," she tells him, pressing a kiss on his knuckles.

"Not too shabby for our first Chrismukkah together," Seth tells her with a twinkle in his eye.

"Definitely my definition of a relaxing time," Marissa retorts sarcastically.

"Sure, there was a healthy dose of family angst but that's par for the course for Cohen-Cooper-Roberts family gatherings."

"Sure, Seth."

"Well, I'm happy," he says pointedly, looking at her fondly. "I got everything I wanted."

She laughs and kisses him. They reminisce about previous holidays and it's light and carefree.

At the end, she's willing to admit, this Chrismukkah was not so bad after all.