Dean can't sleep.

Hasn't much, really, since Hell, but now it's nearly impossible. Even curled up next to Lisa, taking some comfort in the warm soft body breathing within reach, he can't find that elusive peace. Because Lisa, nice girl that she is, is a poor stand in.

Dean flops on his back and stares at the ceiling, Castiel's last words to him echoing in his ears. Be careful what you wish for, he thinks sardonically, not for the first time. With a weary sigh Dean gives up and silently abandons the bed without disturbing Lisa. No surprise, as she's grown used to his frequent leavings. He tries not to find that too depressing.

Tugging on a shirt, he pads down the hall and escapes out the front door. The neighborhood is quiet and still in the dark hours between very late night and too-early morning – too quiet. He's still too used to noise at night; the faint rumble of voices and bedspring squeaks through thin motel walls, the creaking hum of old A/C units, the whirring of tires on the road harmonizing with the growl of engines. This serene block keeps him up more than a busy pay-by-the-hour motel.

The Impala, parked ever-ready at the curb, gleams softly in the dim porch light, and something loosens in his chest slightly at the sight. Lately it seems the only peace he can find is with the Impala, even as it makes his heart ache anew each time.

Carefully he climbs in, gingerly pulling the door shut with a click rather than the customary slam. He knows that if Lisa wakes and sees him out here, she'll worry that he'll drive off, disappear from her life again just as abruptly as he appeared.

He's thought about it. But he's got nowhere else to go, and besides, he made a promise.

Although . . . He squeezes his eyes shut so he won't look at the empty passenger seat and remember Sam's face when he asked him to let him go, to be happy. Demanded it really, the bossy little bitch. And Dean's trying, he really is.

Lisa is everything he imagined, warm and supportive and sympathetic but not pushing. She was cautious when he first arrived, but after a couple months when he showed no signs of leaving she let him move from the guest room into her bedroom. Ben's a great kid, likes hanging with Dean watching movies or learning how to fix cars, and Dean's taught him how to ride a bike and throw a football and cheers him on at his baseball games.

They eat dinner together; Lisa cooks, Dean and Ben clean up afterward. They read the paper over coffee in the mornings, the headlines no longer omens of the apocalypse, and he starts with the sports pages rather than the obituaries. Dean's even got a legit job, working as a mechanic in a garage specializing in classic cars.

He has people who like him, who want him around, even call him a friend. Their neighbors invited them over for a barbeque a couple weeks back, and never gave him the stink-eye look he's used to as an outsider. Hell, they invited him back the next weekend. He's got that white picket fence, apple pie life.

He's not happy.

He's . . . well, he doesn't even know what he is, tell the truth, besides tired. But he's not happy. Given the chance, he'd drop this life in a heartbeat to go back out on the road with his brother riding shotgun. Shit, he'd even take Sam being at Stanford, or married and working as a lawyer, as long as it meant he wasn't locked in a hell-hole with Lucifer for eternity.

How could Dean be happy, knowing what a chance at this life cost his brother? When the memory of Sam falling into the open hole has him waking up with a scream of denial on his lips? When it feels like half of himself has been ripped away, and the crushing emptiness makes it hard to keep breathing every day?

A bitter smile twists Dean's lips. The last thing Sam really asked of him, and here Dean is screwing it all up, as usual. But honestly, how is he just supposed to let Sam go and move on? His track record speaks for itself of how much he sucks at it.

He had Bobby lock the Horsemen's rings away somewhere secret, to remove the burning temptation to open the door and let Sam out, and Lucifer and probably a very pissed-off Michael along with him. Some days he almost thinks it'd be worth it.

Instead, Dean is keeping his promise to Sam, as best he's able. He keeps going, keeps surviving one day at a time, and manages to find a little bit of something worth living for each day. It's all he has the energy for.

Unconsciously his hand creeps up to his chest, searching . . . and not finding. Because he'd thrown it away, the only substantial gift between them that meant something. Dean has a lot of regrets, but right now that's one of his biggest. His hand rubs at the ache in his chest instead, futilely massaging the soul-deep pain.

There is so little of Sam left in the world, Dean has to touch something, to prove that his Sam was more than just memory. That something tangible still exists of the kid who was the center of Dean's world. Clambering over the seat, Dean settles in the back seat and lets his fingers rest on the green army guy wedged in the ashtray, breathing in the scent of home as he leans his head back on the seat.

After the cabin, bleeding out as Sam rushed him and Dad to the hospital, Dean had done this same thing, taking comfort from the memories of two small boys who played and wrestled and slept back here together intermixing with the rumble of grown-up Sam's voice. He'd had a tiny scar from where the plastic gun had gouged his finger in the collision. That one he'd never minded having.

Tracing the small toy, his fingers brush something, not soft exactly, but not plastic or metal. Frowning, he looks down to see a cord gathered up and jammed in next to the army guy. He fishes it out, feeling the tug of weight on it as he curls the leather around his fingers.

His breath catches in his chest as he stares at the familiar gold bull's-head pendant shining dully in the faint light. It's warm, like it'd been worn against skin and just taken off. Wildly he looks around. No one's there, not at this time of night. He's not even sure who would be there.

His heart cries Sam, and Dean wouldn't have put it past him, but Sam's gone. Cas he hasn't seen in months, Bobby either, and neither of them would've had this.

The all-too familiar sting of tears makes him blink, and he's not got the energy or will to fight them. Eyes burning, he slips the cord over his head, letting the small weight fall into its proper place against his breastbone, weirdly easing a bit of that phantom pain.

It's not better, not by a long shot . . . but it's something.

Abruptly the car door creaks open, and Dean jumps, so lost in thought he hadn't noticed anyone approaching. He opens his mouth, about to tell Lisa that he's fine, but the words stick in a large lump in his throat as a man climbs in next to him, long limbs folding with ease of life-long practice into the confined space.

Sam smiles tentatively at him, warm hazel eyes open and longing as he gives Dean a quick once-over, pausing at the amulet. "Hey."

Dean can't talk, can't even breathe. This can't be real. He's dreaming again, or he finally had a psychotic break, or it's some evil fucker determined to mess with him. But it's not Sam. It can't be.

The thing must see the growing suspicion on his face, as it hastens to say, "I'm me, Dean. Just me." It laughs softly without amusement, running a shaky hand through its hair, just like Sam used to. "It's over. It's just me."

Dean shakes his head dumbly, certain this isn't real. It can't be. It's never over with them; there's always something worse waiting to happen.

"Dean."

The sound of his name, so familiar and longer for in that voice, breaks his muteness. "No," he croaks, "it can't be. You . . . you're not real. You're not him."

"I am," the thing insists, reaching for Dean but stopping as Dean recoils from it. Its face falls, resigned sadness in its eyes. "Dean, it's me. It's Sam."

"Sam died," Dean says harshly. This has to be a dream, no matter that he doesn't remember falling asleep. He's dreamt of Sam returning to him ever since Stull so many times he's lost count. "He jumped into the hole, and slammed the door shut behind him."

"Yeah, I know." The thing makes a small huffing noise, closing its eyes for a long moment. Dean tenses, waiting for the moment when the dream turns into a nightmare. Maybe its eyes will be yellow, or the voice will change to the oily smooth tones of Lucifer. Maybe it will be Sam, just Sam, asking Dean why he couldn't save him.

"I'm sorry."

Dean blinks. This is a new one.

"I should've . . . I tried to stay away, to leave you alone. You deserve this," the thing waves its hand around to indicate the quiet neighborhood around them.

"Deserve what?" Dean growls.

"You deserve a normal life, a safe life," the thing, Sam – hell, it's his dream, it'll always be Sam – looks him straight in the eye, genuine sincere puppy eyes cutting him right to the heart. "It's my fault you didn't get that before. And I'm sorry."

He shakes his head, glancing out the front windshield to the dark street before them. "I'm sorry," he repeats quietly. "I tried to stay away, but . . . I can't. I think . . . this is my penance."

Dean's really confused now, but he keeps silent. Even if this dream makes no sense, it's better than reliving Sam falling into that gaping maw, or Lucifer's sneer as Sam's fists slammed into Dean's face.

Sam lets out that wry laugh again, mouth twitching like he can't decide whether to smile to cry. "I . . . I can't leave you. Not now. I get it now." He keeps sneaking looks at Dean's face, like he's afraid to look too long. "You died for me . . . because of me. You gave everything for me. And I repaid you by running away, by failing to get you out of Hell, by turning to a demon. So it's my fault. I killed my brother. And there is no forgiving that."

This can't be real. But this isn't a dream, because despite everything, despite the demon blood and the lies and the betrayal and the fights and all the shit between them, there is nothing that Dean won't forgive Sam. He knows that. His mind couldn't dream that up.

Sam's long fingers stroke the back of the seat, as if trying for the same comfort Dean climbed back there to find. He remembers Sam doing that whenever he was anxious about something, ever since he was a kid, convulsively petting the upholstery like the touch grounded him.

"I tried so hard to keep away, to let you have this life. But I can't. Every time, it's always back to you somehow. Even at Stanford, I always knew I'd end up back to you." He swallows hard, blinking away the wet sheen of tears. "I think I'm doomed to haunt you."

That angsty expression, the hope for redemption while resigned to damnation, that's all 100% pure Sam. No evil bastard could imitate that. In fact, this smacks more of a Winchester miracle, flawed and tarnished and painful but still amazingly good, than another attempt to screw with him.

Despite himself, Dean's getting the sneaking suspicion that somehow, impossibly, this is real.

"Is that such a bad thing?" Dean manages, raspy-rough as hope starts to stir, easing the ache in his heart with every beat.

Sam scoffs, staring at Dean incredulously. "How could you still want me around, after everything?" is what he says.

How could you still love me? is what Dean hears. He's always had the answer to that.

"You've got a life without me. You've got Lisa, and Ben. You've got a job that doesn't require you to risk your life. You've got a home, with an actual bedroom to sleep in instead of crappy motel rooms. You don't need me."

Now there he's just flat-out wrong. Dean has always needed Sam, and will always need him, no matter what life does in the meantime. He sold his soul for his brother, for fuck's sake, because he couldn't live without him.

Sam gropes for the door handle behind him, face scrunched up with pain. "I'd better . . . I just . . . I'm sorry. I'll do better at staying away, I promise. You deserve to be happy, Dean."

Dean's hand moves snakebite-fast to latch on to Sam, so tight he knows he'll leave fingerprint bruises on his arm. "I'm not."

Sam freezes, staring down wide-eyed at Dean's hand on him, breathing hard. "What?" he asks faintly.

"I'm not. I'm not happy, not with this, here." Dean waves his free hand vaguely at the house. "I'm trying, I really am, because I promised you, but . . . it's not my life, Sammy."

Sam swallows hard, eyes wet. Gingerly he touches Dean's hand, flinching back when fingers come in contact with warm skin. "This is . . . this is real?"

"What?"

"I've dreamed this before. We've been here before, in this car, so I could apologize. I keep coming back, seeing you with them, but every time we end up here . . . it isn't real," Sam breathes out brokenly. "It's my punishment."

His eyes travel up to where the amulet lies on Dean's chest, and he almost reaches for it. Instead his hand brushes Dean's again, as if confirming. "But this hasn't . . . you've never . . . you've never touched me before."

Sam's eyes are so wide and full of both fear and hope, the look so patently Sammy that it wipes away any of Dean's lingering doubts. This is real. His brother is here.

Sam's shaking, Dean can feel it, and he tightens his grip more. "Don't you get it? Don't . . . don't leave me. Not again." He doesn't mean for it to come out sounding so pathetic, so needy. But he's too goddamn tired, and his brother is here, not rotting in Lucifer's cage, and he doesn't care how it happened but if Sam disappears again it just might kill him.

So he latches on, and Sam lets him, lets him scoot closer and hug him so tight it has to hurt, but Sam returns it just as strong, holding on as if to never let go. And for the first time since a sunny day in a Kansas graveyard, Dean feels like he can breathe again.

He falls asleep like that, the two of them twined together like the kids they once were, Sam's voice murmuring a promise back to him, "I'm not leaving you."