Hey ssmith, welcome. Glad you found the group -- it's a good place to vent, process, problemsolve, all with people who've "been there done that" too.
Attempting to coparent with a disordered ex is neither intuitive, nor straightforward, nor covered by/understood by "mainstream" divorce books, that sometimes seem to suggest "just be polite and one day, you'll all have Thanksgiving dinner together for the kids!"
I can relate to everything you're saying -- my H and his kids' mom got divorced >10 years ago and the conflict, while "covert" (i.e. there's no yelling, shouting, door slamming, physical altercations), is relentless, pervasive, and unending in terms of emotional/psychological manipulation. The kids are 14 & 16 and while in some areas they've been able to stay strong and not take sides, there are many areas where they are either blind to or totally participating in Mom and Stepdad's manipulation/coercion. It's hard to watch your kids/stepkids "drink the Kool Aid".
You did well to persevere to have as much time with your sons as possible and to be proactive about countering her pathogenic parenting choices.
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Couple of questions for us to learn more:
What do you think may have happened recently to trigger her to pressure your son?
Do you have a therapist through all this? Do your kids?
Does one of the kids seem to occupy one role for her, and the other kid have a different role (i.e. "golden" or "perfect" child, scapegoat/"bad" child, emotional support child/"the little adult"...), that might explain why she'd pressure your son?
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I'm just so tired. I love my kids but I am counting down the days until they are 18 and I can walk away from my ex forever.
Yes. I was just sharing the same sentiment with a friend yesterday night. I love my H's kids, and at the same time, stepparenting them requires a connection (even though we are essentially parallel parenting) with their mom (who has many BPD type traits) and stepdad (many NPD type traits) that is triggering, exhausting, painful, crazy, and difficult to endure.
Keep posting here as much as you need to, and again, welcome;
kells76