You have answered yourself you know.
I'd not choose poly for myself, probably ever.
Here's how I see it.
- You are monoamorous, and love only one person at a time.
- You agreed to be in a polyamorous "V" with your GF who happens to have a husband to try it on. The experiment has failed. You are not happy in this structure.
- You are upset right now because you actually crave a monogamous relationship structure with her. You will not get it with her unless she divorces the husband.
- She expresses wishes to be with you and wishes she could be mono with you. But she doesn't want to leave the husband. Ergo, she is happiest in a poly structure. While sad you are hurting, she is making no move to alleviate your pain by just doing the honorable thing and setting you free and breaking up with you because she sees keeping you here is unfair to your emotional well being.
- You are not happy. It pains you to hear her say she wishes she could be mono -- it's like dangling a carrot you cannot have. It pains you that you got attached to her inside a relationship structure you really do not want for yourself. It pains you that she doesn't decide something so that YOUR decision making becomes easier to do. YOU are not caring for your own emotional well being.
Is that about where this is at?
Then to spare YOU more pain and get your out of gridlock? A decision must be made. BY YOU.
These are your two choices.
1) You must break up if you value your core desire to be in a monogamous relationship structure more than you value being in relationship with her.
If you want monogamous relationship structure and it isn't to be had here -- GET OUT. There is nothing wrong
with wanting that monogamous structure for yourself. And yes, it will hurt to break up -- but there are MANY Right Ones out there. They do not all come at the Right Time or in the right structure for you. Tell your family/friends network you will need support going through the stages of grief as you mourn the loss of a major relationship since you just broke up with someone.
(I think you lean here and you are feeling sad about this. I am sorry you are sad.)
2) If you value being in relationship with her more than the monogamous relationship structure, you must choose to abandon that belief.
Be be fully present in your "V" without adding emotional mess on the side wishing for things you cannot have and will never have in this V structure. Giving up a long treasured belief is painful too -- but beliefs can be changed. If that is the approach you will take -- get your beliefs and actions reconciled so you can be a good "V" partner then. Tell your polypeeps you will need support going through the stages of grief as you mourn the loss of a major belief.
Life choices are not always picking between the "win/lose" thing. Sometimes it is "this choice stinks" and "this choice stinks too." So it becomes a case of "Pick the least stinky thing" here. Whatever it is.
But stop creating angsty gridlock over it within yourself. Do the job in front of you and DECIDE already. Endless emotional stinkage for all is no good and the reason is what? That everyone wants to be shirky about deciding things? Do not want to sit down to have hard conversation?
Well...pressure cooker time will sort it for you then. One of you or several of you will simply blow up fed up with the chronic brewing stinky and things could get ugly.
What is the goal when the polyship changes?
- Be good polypeeps to each other in a harmonious "V" structure where people use conflict resolution and communication skills well.
- Break up the V and be good exes and still friends
- Be angry enemies because nobody wanted to talk real and deal with a THING and time blew it up.
Choose wisely. I already think you are leaning to the bold there. But you really must DECIDE and inform them of your decision.
You have the responsibility to KNOW and STATE your wants, needs, and limits to yourself and to your people.