I haven't been able to respond to your threads but one thing I had wanted to say is if your husband's plan is that you'll all move together to a new state, and will start to live separately at that time - does that work for you? It seems a bit unfair to be expected to move yourself and the kids just because your husband wants to be in a place where his bad actions are more anonymous. You'd be leaving behind your own home and network of friends. Perhaps you want to go too but if you don't then that's an area where you may need some external help to figure out where everyone will live and when.
I know how it is trying to detach with a little kid. You have two, and with a baby you're probably not getting much sleep. It seems it'll be a lot easier when you're actually divorced and your husband has the kids during his custody time. Then you'll have time to yourself to detach more. For the time being it seems you shouldn't put much more pressure on yourself because there isn't much time left in each day aside from caring for the children, working, housework, and cooking. It seems for people in our situations we have to depend more on activities that we can do with our kids and things that can be done at home while they're sleeping like meditation or reading or listening to music.
Perhaps you can do a few one-time things like getting a new hair style, buying some new clothing items, or going for a long walk alone to try to start detaching more.
I just wonder what's wrong with your husband. I was on a family camping trip this past weekend and I was the only single mom among 20 or 30 families. Every other family seemed happy together and were laughing and joking. I saw all the dads, even South Asian ones, caring for the kids and helping their wives. I don't know what's wrong with our husbands who see their family as so intolerable they must leave whereas most husbands love their families and feel responsible for them. What kind of upbringing did your husband have? Did he suffer instability in his family or was he treated badly by his parents? There must be some root cause. Not that you can control anything that he's doing and comparing him to all the great husbands and dads will only make you feel worse, but for me it was a reminder and realization of just how bad my husband really is.
I hope you can learn the right things to say and do to reduce your husband's anger and fighting in front of the kids. It seems like another adult needs to be in the house to mediate. He sounds out-of-control and he's trying to further weaken you when you're already in a damaged and weak state. Too bad you can start living separately immediately to get out of this toxic situation.
I really hope for a quick positive outcome for you, whatever it may be. This current situation just sounds so so difficult and you're doing the best you can.