Wallace,
I think I've posted on your other threads? So many parallels. xW was just shy of 18 when we met, major mother issues, periodic dysregulation written off to PMS, two kids (mine girls), this turned us from collaborative to contentious. As long as we were enveloped in a swirl of effort and activity it was OK, but the "dis-ease" was clear. 39.5 another checkpoint for you? I'd put mine (her's) at 42. Turned into another person - I suspected a brain tumor perhaps. Everyone but BFF and kids split black. Continued downhill, and here I sit 9 years later.
Lessons? Stay as close to the kids as you can. Appeasement will only hurt you, and them. I was able to accept not being able to save her (oh, did I try), but I just can't get over not being able to protect my daughters. They are now well in line to be the 4th generation of that family to carry forth disorder.
Read "Understanding the Borderline Mother", read Childress, particularly about Pathogenic Parenting and its indications (
https://drcraigchildressblog.com/2014/09/11/diagnostic-checklist-for-pathogenic-parenting/). Not sure where you are in the process, but you need a lawyer who understands the pathology and knows how to fight for your time and rights with your children. The team will not do this for you.
Sorry - too many words. PM me any time - I can tell you everything I did wrong... .
Good luck.
My MIL was a vicious witch - she always resented "losing" her abused (by her) and enmeshed (with her) daughter to me. Do not discount the power and intentions of the team. They are not your team. Not for a second.