Hi Live 15, welcome to the forum and I'm sorry for the circumstances that have brought you here. Your H certainly sounds very MLCish from what you post, and it also sounds as though you have been doing well in difficult circumstances.
Clearly he has noticed some of your efforts and the progress you have made. You ask if there may be other 180s you can do. Given all that I read about MLC and MLC affairs, I think it unlikely there will be any short-term fixes here. Actually, short-term fixes aren't great as they are more likely to unravel later.
I think the best thing you can do is truly accept within yourself that he is gone for now, and may be gone for some time. If you can let go and live your life for you for now, that is the best way I think. Tell him that this isn't your choice, but you respect that he wants out and won't stand in his way.
From your sitch, it sounds as though you have been pretty helpful towards him. Alongside being pleasant, I think it's really important to set boundaries. Finances sound like an issue for now, and do take any steps needed to protect you and the children. MLCers aren't renowned for being careful with money. My H does seem to have been thus far, but many get into difficulties.
The second boundary area I think is the whole - I can be part of this family, keep you as a friend and have a lover too. I can have it all! I know you are frightened of losing him completely, but people on this forum always say - they are gone already for now. So, do set boundaries which protect you and allow you to detach from a horrible situation and move forward yourself.
I'm sure others will come along and welcome you. It can feel a little slow to start with and you'll be on moderation at first which delays your posts coming through, but stick with it and you'll find lots of support here.
Take care xx
T 13 M 7 Me 48 H 46 SS 15 BD 7.14 PA D final 5.16 (H filed)
We receive & we lose, and must try to achieve gratitude & embrace with whole hearts whatever of life that remains after the losses - Dubus