Don't engage ExH over this. There is literally no point. You will tie your own hands if you do. He will know that your kids are reporting back to you. You don't want him to know that an sooner than necessary. I'm so sorry for S8. That little should not have to deal with this mess, and as much as I know you want to nip this in the bud, regardless of country, you have to establish a pattern. Establishing a pattern involves you going against your mothering instincts and letting some not so wonderful things happen because you will have to be able to establish that this is who ExH is now. You are blessed to have such sweet boys who look out for each other. If you choose not to battle this out right now it's still better to not approach ExH. Because you will end up with kids who are told to keep their mouths shut or else. As to how he could become this person. This is the person the abused become when they are functioning on instinct vs their higher selves. People like us are wired for abuse, and when put in a position of power, under stress and not in our right minds that monster that's been sitting in the recesses of our minds will rear it's ugly head. The only consolation I can give you here is that person is not the H you knew. That is not who H really is. But it is who H is right now.
Outside of all that ugliness. My dear it's so good to hear how well things are going at the new job, and how well you're doing with everything else. Don't let the mean girl get to you at that place. People who don't outgrow that crap by adulthood have some serious issues. And lord knows if she pushes you she'll learn who she is messing with
