Unfortunately, the reality sounds like you don't necessarily have a relationship right now or at least not the one that you want. And unless he takes care of himself then you're not going to get the relationship that you want. And even if he does, there's a possibility that this does not end how you want it to.

If you're not ready to walk away, then the focus has to be on him getting better. You can't really deal with the relationship until he's in a place where he's able to mentally. If you try and deal with it while he's in depression, then you're just going to be discussing the relationship with the depression, if that makes sense. Super selfish - you bet. Depression is super selfish.

Only you will know when you're done and ready to walk away, but heed the advice that it's a long road. Start by reading Anne's books so that you have some more information on what you're dealing with, and go from there. And come back to the board whenever you need support.

Hang in there.