swedish

I'm sorry to hear of your situation (past and present).

1. Why does he avoid responsibility?
He probably feels he's in way over his head with the debt so what's the point of even trying to get out of it.
2. Why doesn't he recognize any wrong doing on his part?
Based on what you've said about his parents, he doesn't know anything different so he may not have an issue living this way.
3. Can he change? If so, how?
Not unless he wants to and it sounds like he isn't there at the moment. It really needs to come from him (wanting to turn this around)
4. Is this even worth saving?
Not if he's unwilling to put in any effort.
"he glares at me and stands really close like he's trying to intimidate me" This would make me extremely uncomfortable too, especially since he was kind and loving when you met him.
5. What else can I do to make this work?
I don't know. If he is normally a good man and currently depressed, counseling could help him but if he doesn't want help or think he needs it, there isn't much you can do. I certainly wouldn't recommend staying in the situation the way it is.