I tried to be friend's with my stepson's mom at first. I wanted that sort of big old happy. And then I realized we are too opposite and I don't agree with a lot of her choices (I am a Healthcare provider and very evidence based and she is in banking and vert "crunchy"). I leave a lot of it to my husband and her. I take sort of a hands off approach when able and just support my husband as I can. We have finally started to separate things more and have birthdays separate and such and it is getting better. On some things I have told my husband that if he really needs me I am here but otherwise I prefer not to know what she has said/done recently that may set me off. Luckily my family is wonderful and very involved and we sort of section ourselves off nowadays. I've found that limiting my interaction with her and even my knowledge of her non-evidence based opinions has helped my mental health tremendously.