A/N:
This story is based on several premises, which I found interesting to explore:
1.) Sirius and Remus talk – it seems to me, that *because* they never seemed to have talked to each other the whole mess even started. The mess that was Pettigrew being overlooked and not suspected of possibly being the traitor. This was what set up the whole story by JKR in the first place even though it doesn't happen in the foreground.
2.) Sirius and Regulus' relationship – we don't know what their relationship really was like in the last months and years before October 1981 – was it only distanced, was it hateful, or did they actually like each other? I can't really recognise from canon how they felt about each other before Sirius left the family and Regulus became a Death Eater. He merely mentions to Harry how and why Regulus died.
3.) Dumbledore's knowledge or at least his suspicion about the Horcruxes. Since he collected all these memories about and around Riddle I'm pretty sure he knew even at the time of the prophecy that Voldemort had something up his sleeve and possibly even what it was. Prove of this claim is the memory fragment from Slughorn, the one where Riddle's mentioning of Horcruxes appears. This is probably the weightiest premise in this fic.
4.) IF Voldemort never gets to neither the Potters nor the Longbottoms, THEN he never marks the one with the power, etc. Therefore, the whole prophecy falls flat. AND if they actually know about the Horcruxes, THEN Voldemort can be vanquished by anyone once these obstacles are out of the way. There is now no Horcrux in Harry after all. Voldemort can only believe in his Horcruxes as long as no one else knows about them. In canon, Regulus must have learned about their existence somehow, and he must have known, or at least been able to conclude what they were and did, otherwise he would not have ordered Kreacher to destroy the locket. Voldemort's secret gone means he becomes very, very vulnerable.
Albus Dumbledore keeps a Secret
Prologue
February 1977 – Gryffindor 6th years boys' dormitory
I'm waking up and have to breathe deeply to stable myself. Once again, I've had that horrible nightmare of killing my best friends while transformed to the monster – especially the boy I know I'll always love more than my life. I close my eyes again, but the image of a werewolf tearing a human body to pieces – a human body that strongly reminds me of a boy with long black hair, bright grey eyes and a permanent mischievous grin on his face – just makes me shake!
Exactly said boy carefully opens the drapes on my four-poster bed.
"Remus! Are you alright?" he whispers.
"Yes, I am, Sirius. Just a nightmare…"
He moves his whole body inside and I budge over a bit to give him space. Sirius makes himself comfortable and wiggles to pull the cover over himself, too.
"You don't need to stay with me, Sirius… the dream is over…"
"I know, but you never sleep well after a nightmare unless one of us is with you. Moony needs someone close. You need your sleep, you know we have a difficult test in Potions tomorrow…"
With that he puts his arms around me. If feels wonderful and I start to think there's more in his embraces. It's been a while since it was James who did this. James has always done it because, as he claims, Moony needs closeness to other pack members, but when Sirius does it, there's another quality in the hugs. I don't really know if he feels it, too, of course, but since it feels different for me, I suppose it also feels different to Sirius.
"How come it's always you who comes to me, lately? Wormtail's never come in to keep me company; I think I scare him. James hasn't come for a while now," I ask.
I can feel his smile.
"Because I want to, Moony. I love to feel close to you."
"I love to feel close to you, too, Sirius," I whisper in response.
"It's because I love you, you know…" he dares to go on.
"I know you do. I love you, too…"
"I mean, I love you more than just a friend," Sirius says.
That wakes me up completely.
"I'm not sure I understand…"
"I love you, Remus. You're a boy, I know, and you might be completely turned off now, but I just had to tell you. I thought I'd felt some of your feelings, too…"
And as I turn to him, we look into each others' eyes. Even in the darkness, I'm sure to see the light in his eyes. They shine with so much warmth! I can't believe it! He loves me! ME! The skinny boy who becomes a monster once a month! I'm 17 now, but I'm still skinny and awkward and shy. I know I'm collecting academic honours at the school and I love my success, but I'm still lacking many social skills.
However, so does Sirius. He's nothing like me, he's neither awkward nor shy, but he has to rein in that arrogance, with which his snobbish relatives have raised him. He sometimes still has problems to let others see his ability to show love, compassion, and understanding. Lily Evans still won't believe me when I tell her that both, James and Sirius, are warm hearted and friendly, she still only sees the arrogant prats.
So here Sirius is – admitting his love for me. Can I tell him that I love him just as much?
"…you can tell me absolutely everything, Remus, always! Never fear saying anything to me, because I want you to tell me whatever goes through your head…"
Did I just say that out loud before? Or has he used some Legilimency? I'll never know, because I tell him now and again that I love him back and that I'll always love him.