Poly is about love. Not about not having love but expanding it. If you were to identify as poly then you would need to have the best possible relationship with your wife before finding more partners. Poly is not about filling in the gaps but expanding what you have already.
It sounds like you are ready to move on from your marriage. Not easy, but necessary sometimes in order to live to our best possible potential. Yes, a site for marriage advice might be better, but you also may find, in reading here, that you will learn something of what you should do next in your life.
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