Do you get along with your step kids other parent?

I absolutely LOATHE my husbands ex. We both do lol. She’s the nastiest person I have ever met. We got custody of his kids in April because she’s just absolutely crazy. Not a “bad mom” or anything, but a shitty person and you the kids got fed up with it. I swear every other weekend they go over there SOMETHING goes wrong. She always has something to complain about. I have gone out of my way to be sooo nice to her, especially since I became their full time mom. I wish we could all be civil but she’ll never allow that.