Oh and I forgot to say: one day, AH told me that I'd better watch what I was doing because the kids might end up with no parents at all. I, of course, took this as a death threat. So I promptly bought a tiny digital recording device and secretly recorded conversations we had in which he was intimidating, abusive, manipulating. I made my psychologist listen to these conversations and this helped me tremendously to understand every manipulative tactic of his. Also, I felt I had regained some control as I had proof of the abuse, and proof of potential further threats.
Again, all I can tell you apart from taking your security matters seriously is to build a solid support system around you so you do not need to rely on your controlling AH as far as children are concerned. It is interesting to see now how my AH absolutely hates my friends because he knows that because of them, I don't need him any more and therefore, he has no more control over my life.