I believe that it's possible to care deeply for someone, despite their inner turmoil. Yet, which part is love and which part is pity/caregiver?
If you just don't think that you can hear anymore of whatever it is of his baggage that he unloads onto you, then would seem you're burnt out on therapy services that you are giving to him as a caregiver?
Fear of him hating you, contradicts that stuck feeling of being unable to get yourself out of the relationship.
Wouldn't he also hate you if you broke up/ended the relationship? What makes this different?

It's truly a rhetorical question.

I recently saw on my former sister in laws fb feed one of those quote styled memes. That when someone tears at another person's character so terribly, that it's a mask for all the awful things they themselves had done.

I left her brother. I'd also experienced going through three restraining order hearings plus one renewal.