I'm anxious to hear what your C said. I have to admit though that I had a disturbed reaction to your post telling us that all of your daughters are disconnected from your W and avoid her.
With each of your posts it seems clearer and clearer to me that you and your daughters would be happier removed from the situation. It seems to me that you are staying for your W who is the cause of a large portion of unhappiness in your household....for you and your daughters. That just seems like a largely misplaced loyalty to me. I'm not saying that to be mean at all. It just appears to me that you are staying more because you gave her your word that you wouldn't leave, not because it's the best/right thing to do....so come hell or high water you aren't going to break that word.
I know you said your W believes M is forever...and sure, ideally it is. I think too that too often people give up and go for a D without really trying. This does not apply to you. I'm not trying to tell you what to do, I'm just giving you my perspective on your sitch. You have given a Hurculean effort towards your M. If you do leave, and your W feels abandoned....you know what, that's her problem. It also doesn't matter if she ever takes accountability if you leave, she most likely won't as someone with NPD. She won't tell others that she contributed to the problems...because she doesn't think she has. You know different.
