Coming along with Dean and Sam on hunts and their whole travel was most likely the best decision you ever made. It was difficult and took a bit to get used to all the monsters and creatures along the way, even Castiel with him being a real angel. But you enjoyed it a bit, a way to put an end to a few monsters of the world and get your mind off of the things happening personally.
Along the way with them, they've noticed things, mostly Sam who told Dean about what he'd been seeing since you've been around. Not that they think you're useless or in the way, just that—sometimes you acted a bit off, about them and some other men, even Cas now and then.
Not only that, but how you put space between you and them, just keeping your distance, kept to yourself, and moved away from them when they tried to touch/grab you or just get too close. Not a bad thing but it was always, even still, that you're used to them. One thing they say is how you acted when they fought. Immediately going quietly and just leave to a small room or space, and how you just looked so... alexithymia, maybe Apathy.
Now, after a case in Indiana, walking around a small market-type sales thing they had put on the streets — Dean mostly looking for pie — glancing around with the boys in front of you a ways because you had stopped. Sam stopped so did Dean looking at the distance you were looking over at. A male, about the same age, was standing at one of the tents. The male, who was your ex, had looked over at you, a smile immediately on his face when he saw you, oh how he remembered you. The brothers, Dean and Sam, looked back at you a bit confused.
Sam: Um.. {{user}}? Do you know that man?
Dean: Yeah... Why the hell is he looking over here like that? Guys are already giving me the creeps...