I feel for you. I am experiencing something similar in my life... mono partner that is not interested in and does not have to capacity to be able to stick around if I am to live to my fullest potential in poly.
I have made a choice to honour him and what we have and dull my nature down. I am willing to do this to see how my love expands with him, not with another man I love.
I was not convinced for some time that I should have to make a choice between men, and put myself in a situation where my mono partner considered my actions to be those of a cheater... I was heart broken, as I didn't think so... but that doesn't matter, I broke our agreement and I needed to own that and find a better path.
It is VERY easy to jeopardise ones ability to "not touch" by putting yourself in situations where it "could" happen.... "could" eventually becomes "will" for me... so I will avoid it. You know your own nature... you decide what would be a situation that you could cheat in and avoid avoid avoid. Cheating is not the answer as far as I am concerned... do a tag search and see what the results have been for those who have cheated. Quite often they are grim.
As to whether this is worth it? To me it is, but then I have an amazing relationship with my mono man and I have a lot to lose without him in my life, far more than what I would gain if I were to add another man... not only that, but the situation has brought us closer together and we are better as a unit because of what happened and who we are in our natures...
Ask yourself if this partner is worth being with... what are the pros and cons? what is to be gained by leaving? what is to be gained by staying? Do the math and then start moving forward.
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