I agree that C is needed, but perhaps even more, a genuine desire to change as evidenced by observable changes in their lives. I am kind of a geek and have been reading a lot of books/journal articles about brain networks and how to change destructive behavioral patterns since my XH dropped the bomb. Long story short, psychotherapy is the most effective way to alter brain networks associated with certain psych diagnoses, including post-traumatic stress syndrome and panic attacks.
Even if the D is finalized, changes can still occur in your H. I am 21 months post-bomb and 6 months post-D. It's very odd, but I feel as though my XH is beginning to poke his head out of the tunnel a bit here and there. He has been letting down his guard with me and I think even finds comfort in our friendship. God and the universe has really brought a lot of significant challenges into his life since he left that have begun to humble him a bit. I have been consistently loving to him throughout this time. I think that this is the key.
Keep putting one step in front of the other and be grateful for every day you are given.