Bipolar: Which way hope?

I have a friend who has gradually come to realize (and now has the diagnosis) that her husband is bipolar. He doesn't have hallucinations or delusions on the level of the psychotic, but other than that, he checks all the boxes.

He had an affair (well, one that she knows about, because he is secretive and has large chunks of time which he does not account for), about which he says "Ok, I made a mistake." He makes grand financial gestures to help people, without telling his wife, and continues to want to keep all his financial decisions secret. He does not want to take medication and he wavers about whether he "believes" his diagnosis is correct.

Obviously, she has the right under canon law to severe the common conjugal life, because of this long-standing affair. I'm asking those of you with this disease and those who are (or have been) married to someone who has it: if nothing changes in this scenario, is there any hope for her marriage? I'm thinking not, but I'd like to hear what people in the know have to say about it. More to the point, is there a change that would significantly improve the chance of survival for this marriage? If so, what is that?

Oh, and he has "anger issues". That makes me think this situation is too dangerous to stay in....thoughts? :(