It occurs to him, at some point between his seventh cup of coffee and a constant flow of Led Zeppelin that only he can hear, that if he died, he probably wouldn't wake up. It's not an Earth-shattering revelation, there's no fanfare and fireworks, just a quiet realization while his brother drives an unfamiliar car.
It's funny that he has to remind himself that he can go to sleep and never wake up. Normal people don't need to do that. Normal people live and die only once.
Sam is afraid to attempt suicide. Not because he's scared of death. After Cold Oaks, the reapers in Greybull, their trip into Matrix-Heaven, well, he's afraid of waking up again. Suicide is the last hope of a desperate man, and even that option was taken away from him. Besides, they say that suicides go to Hell. Sam knows that he's no longer in the cage - probably - and he's not entirely keen on going back. And then there's Dean. His brother has given everything for Sam, so he has to give everything for his brother. It's the Winchester way, self-sacrifice for a moment's peace. Dean wants him to be okay so badly; he can't bring himself to shatter that illusion.
So he ignores Lucifer as best he can, consumes enough caffeine to make his heart stop, and runs on the hope that he can keep going until he can't anymore.
And then, suddenly, he can't anymore.
Frank's most likely dead and the Leviathans are curing cancer and he hasn't slept properly in over two weeks and his body hurts and nothing makes sense anymore. His whole world is a mess, was a mess, will always be a mess, he comes to understand, and he doesn't want any part of it anymore. He's defeated the devil, suffered in the blackest part of the Pit - he's done enough.
Lucifer waits until Dean leaves their motel room before starting his new diatribe. "Man. He looks tired, don't you think?" And dammit all, he does look tired. He's tired and sad and hurting, and he hasn't been the same since Cas walked into that lake. Frank, Bobby, Cas - Sam is his only pillar left, and he is rapidly disintegrating.
Dean has said that they keep each other human. Sam traitorously starts to think that he was better off with only Castiel. "Probably," the devil concurs, leaning against the wall casually, "they had that 'more profound bond' or whatever. Sounded like they didn't really need you." He struts around to the other side of Sam's bed, sitting down and leaning against him. Sam can feel the weight of him against his back, and he feels sick, he wants to cry, he's done his time, he doesn't deserve any of this, and he would have been okay if it weren't for - "And anyway," Lucifer says, smugly, "didn't Cas do this to you? Knock down the Great Wall of Sam for a bargaining chip?" Sam shakes his head, unwilling to open his mouth, in case he vomits. "Pretty sure he did, bunk buddy."
He shakes his head again, desperately trying to quell the old thought that Cas didn't like him, never cared about him, only saw him as a tool for Heaven and Hell, and the older thought that Dean would be so much better off without Sam's baggage weighing him down. "It's true, Sammy," the devil whispers in his ear, and it hurts because the devil doesn't lie.
And this devil only speaks the truth that Sam is too afraid to face.
He pinches himself, the sharp jolt of pain waking him up for another five minutes. Lucifer starts humming. Again.
Sam vows, right then and there on that lumpy motel mattress, to overcome the devil, for good this time. Pain and coffee aren't working, so he'll just have to stoop to more drastic measures. He thinks of Ruby's blood, and reminds himself that this isn't the first time he's done something stupid to save someone he loves.
Sam's a smart guy. He'll figure something out.
