It was the during first crossroads deal that he saw that the idea first entered his mind. It was brief, fleeting - nothing to dwell on. He wasn't even sure where the thought had come from. His only guess was all the times his father had drilled it into his head to "keep Sam safe". That was it; nothing more there. The idea came and left, and he didn't think about it again for a while.
That was it though, as he had realized when his lips met with the demon's to whom he had sold his soul to bring Sam back. He didn't have to think about it. Sacrificing himself for his brother was a reaction, an instinct rooted into the very way he existed. He didn't have to think about it.
Maybe that's why he should have noticed when his mind kept coming back to the same idea time and time again.
He'd thought about it a lot, actually; more times than he'd admit to himself, but he'd planned it out carefully and put a lot of thought into it. He'd danced around the idea for years, but there had always been something holding him back, something stopping him from deciding. There was the apocalypse - his fault, really; he'd broken the first seal - Lucifer, Eve, Lilith, the leviathans, demons, monsters, something...but now there was nothing, and he was ready, fully decided, fully committed.
He'd made his mind up for sure when Sam left Amelia for the final time. He saw how much that hurt him, but more than that, he saw that Sam really did find a way out, and a different life for himself. As Sam had pointed out, Dean himself didn't. He couldn't picture himself outside of this life; hell he could hardly picture himself with this life - with any life. He was meaningless either way.
All the times he'd so willingly lain himself down for others, he'd told himself that he cared about other people. Truth was, he just didn't care about himself. He'd done way more bad than good, and he was more alone now than he ever had been before.
Him and Sam had worked separate cases a few weeks back but had carried on that way after that, only connecting with the occasional phone call. Cas was no where to be found and hadn't been in months - Dean had given up on him coming back too. Everyone else who might've cared was dead. He had no one left and nothing to do. He was done, and so why not make sure Sam was safe before he left?
He knew that if he waited it out - life, that is - he'd have it easy. He knew he'd make it to Heaven, and everything might just be alright. If he was being honest with himself though, he didn't want that, didn't deserve that. He didn't want to have eternity alone in one of his only decent memories with nothing but his thoughts to keep him company - thoughts that would do nothing but remind him of why he didn't deserve to be there. His father died because of him, he'd let Sam die so many times it hurt too much to keep track, he'd gotten Cas killed a few times as well, Jo killed, Ellen killed, Bobby, Ash, Kevin, - Lisa and Ben almost too, Charlie - and those were just the people he was closest to. They didn't even begin to rack up to the strangers and people he barely knew. Everyone he came into contact with was at risk. He deserved Hell for all that he'd done. Really, in doing this, he was only getting what he had coming. He was setting things right.
With that as his conclusion, he popped open the trunk of the impala and pulled out the box that he'd carefully put together months ago when he first settled on this ending.
He didn't hesitate as he walked to the middle of the crossroad and started digging; he'd done enough waiting for this already. It was time now.
He set the box down in the centre of the hole he created and kicked the dirt back over it, waiting. It was only a matter of seconds before he heard a voice sound from behind him.
"Well well well, Dean Winchester. To what do I owe the pleasure?" The new arrival purred, in the form of a slender, black haired woman. The newest replacement for all the previous crossroads demons he'd slaughtered.
"I want to make a deal." He said, getting straight to the point.
"I figured that much, sweetheart, I'm just trying to figure out what it could be. Someone to love you? We both know they'd end up dead - even you're not that stupid. You want daddy back for a family reunion? He's long gone now, but that's not what you're after either, is it? So what could it be?" She mused, a satisfied smirk plastered on her face.
Dean supposed that he should feel annoyed, or angry. Maybe the old him would have. Right now though, he just...didn't care. He didn't feel anything. The whole ordeal should have made him feel nervous, or scared, or regretful, or relieved even, but there was nothing. He was painfully numb inside, and it was with that lack of feeling that he answered.
"I want Sam out. I want him happy. That's the deal. No demon ever crosses his path again, no monster, no creature, nothing. He finds a nice girl, settles down, and hunting becomes a thing of the past. His life for mine."
The demon raised an eyebrow, though made no other immediate show of emotion.
"Always so eager to sacrifice yourselves, aren't you Winchesters?"
"This will be the last one."
"Are you telling that to me or yourself?" She asked.
Dean didn't answer.
"Alright, well what makes you think I can do that anyway? We don't control monsters."
"I've seen what you black-eyed bitches can do. This is nothing."
"I'll tell you what," She started, her eyes narrowing, "I'll give him all that, and I'll throw money in on top of it, no strings attached, you get one year only."
"No." Dean said flatly.
"No? Look that's the best offer you'll ever get, so take it or-"
"No. I said no. I don't want a year." He repeated.
"If you think you're getting any more time, you're-"
"I don't want the year." He cut in again, already tired of waiting.
There was a moment of silence as the girl - demon, really - let that sink in.
"..You mean?"
"Yeah."
She paused.
"Guess I shouldn't be surprised," She said finally with an amused laugh, beginning to pace around him, "it's no secret how dead you are inside. Looks like you're just eager to match."
Dean ignored that. He didn't want to admit she was right.
"So do we have a deal then?" He pressed, his tone mildly anticipating.
"Do we?" She countered, stopping to look him in the eye, searching for any hint that this might be a trick.
He met her gaze, knowing she'd find none.
She looked away first, and they fell into silence for a second as Dean closed his eyes, taking in his surroundings for the last time.
He'd intentionally picked a road that was practically abandoned. There would be no distractions, no interruptions, and most importantly, no people to find him right away. There would be a few days at least until anyone discovered his body, and he figured a few days after that until Sam heard. He knew Sam would put it together right away, he was clever enough, but he hoped his brother would leave him alone and not try to bring him back. He'd probably come for his body - mostly to salt and burn the remains, but there would be no need. Dean had no unfinished business, no one to seek vengeance on. He had no intentions of coming back. He was finally ready to die. If he thought about it though, he had been for years.
He opened his eyes again and inhaled deeply, breathing in the finality of it all.
"We do." He said, his voice much more calm than it should have been, and that was it.
She closed what little distance was between them and brought their lips together, sealing the deal permanently.
He heard the telltale barking of the hell hounds nearly the second he pulled away.
He hardly had time to register the small smile he wore before he felt teeth and claws digging into his body, ripping mercilessly at his flesh. Pain was everywhere, searing though his body...and then there was nothing.
A few days later, a few states over, Sam Winchester picked up his phone, dialling the number he'd always know by heart.
He wasn't surprised when it went straight to messages.
"Hey, Dean, sorry I haven't been calling lately. I've been busy over here and I- I met a girl, and I think she might actually be the one. I know you wanted me to go out and make a life for myself, and I think I have. I know it sounds crazy, but she's perfect. Really perfect. I want you to meet her. Are you still in Wyoming? We'll be there soon. Call me back."
The message cut off with a beep, and the phone shut down, laying lifeless again on the passenger side of the 1967 Chevy Impala, only a few feet from where its owner lay shredded on the corner of the crossroads.