Thanks, Nomo, for that very honest, direct, and thorough response! It helps a ton. In fact, I haven't responded to H's latest email since I read your post, in which he asks for more clarification about where I am (in a way that provokes me very effectively to want to respond). I need to sit with it a while. And he's asking for input about where he is, which is weird. But more about that later tonight, when the littles are asleep.
I'm about to go have dinner with the ILs, but one brief thing here. One thing I realized is that the basis for my love for H was the fact that he loved me. Now that he doesn't (in the same way), all that's left for me is his grumpy self and my wish that the kids didn't have to go through this. That's not a lot to work alone to save an M on, is it?