To a certain extent here, I am assuming he was honestly trying. There's always the chance he really is just an asshole who was being manipulative.
All I can say is that when people get stressed out they start doing mean things to each other. I have to think some of these things are things he did not to be mean, but because he didn't know healthy ways to end things or get space, so he was unkind instead.
I don't really know the whole story here, I am making some guesses based on my own history, my own relationship mistakes. I can never truly have the right answer here. If I'm lucky, some of the things I say may help you figure out that it's possible to care about someone and still not have it work out, just because everyone is still learning.