So this guy is her dom? He sounds like an asshole. Sorry, but its not a good dom that makes a woman force her husband to do as he says. Its also not a good dom to force a woman to have sex with someone she doesn't want to by taking away love and connection if she doesn't. I suggest you hold on for dear life and fight with everything you've got to get her away from him. He is not poly, he is abusive in my opinion. Poly is about consideration/empathy/compassion, consent, open and honest communication and integrity. This guy is missing all of these points but the communication and your wife is just skipping along with everything he does.
What did the ex wife say about him? It sounds like he has some issues about control to work out. The red flags are waving big time for me. This sounds like a very harmful situation, especially if she has self esteem issues.
I think that she is likely being more damaged because of this man. Keep talking and being honest... you won't get rid of undue stress, but it does get easier. I don't think that there is anything you can do that will MAKE her want to explore some of this stuff with you, but if she is wanting a man to control her life, then I suggest you rise to the occasion and give it all you got against this guy... all the while doing it with empathetic love and respect for her in every way... which is how he should be treating her.
I suggest doing a tag search for "lessons" "foundations" "mono/poly" "BDSM" "communication"
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