I too had a very physically & mentally abusive marriage when married to my FWH#1. He is the one who had the affair though, not me. But the abuse was SO much worse & more frequent at the end & I wondered why. I now have confirmation that it was probably because he was in his affair at that time though so the puzzle pieces just keep falling into place for me.
BUT......after I finally got the courage to leave his ass because he came close to killing me one day, I then slowly came out of the abuse "fog". (yes, people, there are so many statges of DV that fit statistics just like having an A that all tend to fall under the same types of traits)
It took quite a while to get my self-esteem & courage back but leaving him was the BEST thing I ever did for myself & my 2 boys. I think back to those 10 years of hell & cringe that I stayed so long.
And I can only imagine how much worse it is with your A!!! Now he feels he has a true reason to be this way & it won't stop until you step up & leave him. (or he gets some major DV counceling at the very least)
Kids adapt....mine were 10 & 4 years old & they understood so much more than I gave them credit for & were so much happier without the conflict, fear & violence involved in their everyday lives.
I wish you luck & am sending many hugs your way!!!