One thing I don't understand in your situation, and I think this affects how i read the rest of your account. So I feel the need to clarify before commenting further.
Your "poly partner", who is the person who lives far away from you says that he wants you alone and doesn't want to share you? How is that statement in any way compatible with being poly? Did the other person accept that you were not going to be leaving your husband, and were looking for a true poly relationship? Why did that change?
Because as I see this, this has nothing to do with your husband or his restrictions, or you being poly, but has to do with this other person changing his mind and expecting you to change along with him.
Please check out The Birdcage - an open, friendly Polyamory forum for all parts of New York State
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