My god this is exhausting. Are you a bad girlfriend? I don't know because this is all about YOUR EX. who you were perfectly fine to and is now YOUR EX.

You dated this ass for six months and only three of those were worth anything. His background and childhood is all very teary but has nothing to do with you.

What you do now is stop taking to him. Stop hanging out with him. Stop crying to him or about him. Just stop. Expect nothing from him, because so far that's what you've been getting.

I'm sure you are a lovely person OP, but you are 23 not 13. You have nothing to apologize for, especially to him.

Start taking care of you and figure out why this ass is still a thing for you emotionally.