If he's not willing to make any effort to salvage the relationship, I think you have two choices: You can resign yourself to being the sole support of a man who isn't willing to help himself, or you can end the relationship. If you really think he's going to kill himself, call 911 on your way out the door--and I mean that to be helpful, not snide. You cannot save this drowning man. All you can do is summon help for him, and then save yourself.
He'd go so far as to kill himself if you leave, but he won't make any changes?
At the time I was having other problems too, he was obsessed with touching my bum, it was a constant, every day thing.