A/N: First off, Spoilers through Season 4. Secondly, this is set in "Lucifer Rising" just a bit before Sam goes to kill Lilith. Other than that, enjoy!
For a moment, Sam wishes things could be normal. Not what most people think of as normal, the normal that comes from living in one town your whole life, with your mom and dad and big brother and white picket fence. He tried that kind of normal once, with Stanford and Jessica. He enjoyed it at the time, he thought, but now he can look back and see it for what it was, hollow. He knows now that he wasn't meant for that kind of normal, and any chance he might have had at it was lost the day he turned six months old.
No, what he wants isn't an apple pie kind of normal, but a kind of normal that goes with a life littered with shotgun shells and bags of salt, a Sam-and-Dean normal. He wants to stay in cheap motels and eat greasy diner food and drive long hours in the Impala. He wants to hunt vengeful spirits and Wendigos and maybe a vampire or two. He wants all demons to be solitary and selfish, all angels to be a matter of faith and for the only thing they have to worry about between monsters to be whether they have time to stop by Bobby's for a beer.
He wants all of that, but he would trade it all to get back the trust, implicit and total, between him and Dean that somehow, in the midst of all this crap, got left at the wayside. He misses not having to worry how he's going to get through this one alive because he knows Dean will always be there to save him. He misses knowing that, no matter what he does or says, Dean won't ever think less of him. He misses believing that there was nothing in the world that could possibly go wrong that they couldn't set right again together. He misses telling each other everything because there's no need for secrets from your family. And most of all he misses the way Dean's eyes used to shine with pride and absolute certainty, declaring to the world that this was his little brother Sammy, the best one of any of us.
Whatever else Dean might think of him now, Sam isn't stupid. He knows he can't have all of that back, hell some of it he never even had in the first place. Some of it he knows never really happened except in the rose-tinted memories of "the better days." He knows that some of it he might have had at one point, but the world's changed too much between "now" and "before" for him to ever have another chance at it. And some of it he knows he'll never get back because he gave it up, sacrificed his own happiness for other people and for Dean.
He can't help the small smirk of amusement in response to that thought, because if sacrifice doesn't count as a Sam-and-Dean normal, he doesn't know what does. So, for a moment, Sam closes his eyes and clings to the small bit of normal he has left. Then the moment's past, and he opens them again and drinks.