Because Steve is trying very hard to not put any pressure on the other man to be anyone he doesn't want to be. Somehow he's decided it's easier for Bucky -- for Soldat, if Steve isn't around all the time. If he keeps his distance. And it's hard, but hell, Steve is willing to do just about anything to make up for sleeping while his friend went through hell.

He visibly flinches, brain helpfully dredging up crystal-clear images of the fight on Insight C. "You didn't. You saved my life," which comes out a little hoarse, because. You know, emotions are annoying.