Poly with heirarchy and veto rights is not how I roll, so it would be out of the question. I am not okay with someone telling me to dump someone because THEY are struggling. Not my husband, not anyone. So I don't ask for that in return. I have earned my integrity and my partners trust that I have their best interest in mind in all that I do. Vetos are built out of fear and lack of trust. I don't find that a useful way to live.
Your impatience, frustration and need for "no drama" is no reason to insist he end it. Its not for you to decide. You have no control and shouldn't have control of his life and choices. If he decides its not worth it because you keep telling him what's going on for you and how they're actions affect you and others then that would mean its been up to him. As it should be I think.
We have discussed vetos here at length if you are interested in why anyone would avoid them. Try a tag search on "veto" "vetos" "veto rights" "veto power"
To me this woman just sounds new to poly and your husband; smitten. They fucked up. It happens. What they do about it and what boundaries are agreed upon as a result are what is important. What are they doing to ensure that you can trust them? Integrity is so important in poly dynamics. It takes time to build and even more time when someone fucks up on an agreement.
I would be letting them know that you won't be rescuing them by cutting into your date time again either. It seems that they weren't all that grateful anyway so why bother. You got nothing out of it that was positive so why allow that to happen again.
I think I would find some empathy in this and remind myself what its like to be sucked in by someone that is new and exciting in your life. I would remind myself that I am dealing with two people drunk on emotions etc. And do my best to laugh it off. This is possible, I think, with firm boundaries constructed from the experience you have with them together.
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