I think it is a good thing that he is not giving up on the relationship. He realizes that he needs help and that if he continues, he is going to lose the relationship. He is many steps ahead of other addicts who use and abuse others because they think it is their right. I would just let him be, when he is ready he will come back to you. And it sounds like he will be doing even better for both of you whenever that time comes. Just be there if he needs it, but step away if he doesn't. Trust me, I know this is hard.