\\Does it feel that your life's become a catastrophe?
Oh, it has to be for you to grow, boy.
When you look through the years and see what you could
Have been oh, what might have been,
If you'd had more time.\\

The years Sam's at Stanford are the longest four years of Dean's life. He fills the time with hunting any goddamn thing he can find, but the loss of his little brother after having him in his life nearly 24/7 for eighteen years is devastating.

The first few months he nearly gets himself killed several times on routine jobs that he's done forever, and he feels twelve again when his father reams him for his failures. After that he somehow pulls it together and moves on, but Sam is always a thought in the back of his mind, a feeling of I wonder how he's doing and he's better off without us anyway. Because he knows Sam's destined for something more than this hunt, than dying a gruesomely bloody, disregarded death in the middle of fuck-all nowhere, USA.

It's still a relief when Sam agrees to go with him to Jericho. For a moment it feels like old times, like everything is going to be okay again. Their family can be whole, or as whole as they're ever going to be. But Sam blows that feeling straight to hell, and all Dean hears is this voice from four years before echoing in his head, you are so scared of that fade to black, of living a normal, safe life, that you'll just do whatever the hell Dad asks you to, no matter your chance of survival. Well I've had enough of following orders, of putting ourselves in danger for people who don't even care. I can't do this anymore.

Lies, all of them. Because Sam can, he shows it with the woman in white, and again on his own crusade after Jessica's death. All he needs is a push to get him started, and Dean knows he'll never be able to stop. There are some things you can walk away from, and some things you can't. Some things you forget, and some you never can.

Bonds go both ways, and though Sam may have tried to cut the one he has with Dean, that wasn't ever an option for Dean. Family is all he has. He hasn't had a home since he was four and cradling baby Sammy in his arms, the heat of the fire licking the back of his neck like impassioned vengeance.

Somehow, though, when he's with Sam and Dad, it doesn't matter too much. Because a real, stable house may be a nice thought, but home is something only he can define. And for Dean, home is just another word for family. It may be all he has, but it's all he needs.