I'm learning a lot from this discussion. I have two comments:
I think they meant it when they have a moment of clarity and say I'm sorry. It is not the I'm sorry of repent/remorse but they are really sorry. Then the fog comes over again, or something takes them deeper again and it is back to anger and blame us.
I remember the moments of clarity in the earlier days with my H. His eyes would clear, he would hold me and say that he can't believe he's done this, he's sorry, he loves me so much. And I remember one time I looked at him and said, "you're going to go away again aren't you?" and he replied yes. We both knew that the fog would come rolling back in and the stranger would reappear. So very very sad. In his moments of clarity our love and connection would fill the room but the fog would suck the life right out of the room. So bizarre but always validated to me that this was an illness and out of my control.
On another note re: remorse - I have become so sick of the words and no action from H. Don't tell me, show me. In the last few months I have seen the biggest change in him regarding our two young children. It's the most consistent he has ever been in their lives. He's on every detail, sometimes emailing me to remind me of what's going on at school, such and such needs this, etc. He's really learning to be a father. I would love to see that consistency in our marriage however at least he's showing what I believe to be true remorse for being an absent father for the better part of their lives. I'm hearing less and less about "poor me, I've really screwed up as a father" and much more action. Maybe someday that may just carry over to our relationship. Who knows.