Hi HaWho, sorry that you find yourself here, but welcome. You have been getting some great advice from some of the best so listen and learn.
My advice is to read everything you can about MLC, it really can help make some sense of what to expect from your h. Next thing is don't take anything h says personally and don't believe anything he tells you either - he will say and do anything he pleases, whether to get him out of a sticky situation, whether to try hurt you or just because he can - build armour quickly - it can get very hurtful at times.
Sadly this is the start of a long journey and no ones knows how it will end. All you can do is let your h go on his journey into crazy crisis and focus on yourself and your kids now. Try to do something nice for yourself everyday, even if it is just a walk in the fresh air or a bath, its important you are kind to yourself and look after your mental and physical well being - especially for your kids, they need a stable parent and right now you are it.
HaWho, I really feel for you, you are doing great,hang on in there, look after yourself