stanss:

“Steve has this part of him where it’s Bucky and Peggy from his old life. And then he has a new family and this movie makes these worlds collide. […]  The loss of Peggy certainly made Bucky the last remaining part of his old self. He’s remembering home, who he is before this shield. When he lose Peggy, Bucky becomes so much more meaningful. That’s what motivates Steve to become selfish. You got the most selfless guy in comic books all of the sudden saying, ‘I care more about my relationship than what it means to you guys. [The guy’s only] looking for home and he’s found it with the avengers. […]”