It's funny, when my (ex) husband and I opened our marriage to polyamory after 20 yrs of marriage, it came as no shock to him at all that I felt I was poly. My "roving eye" and tendency to get crushes was always there, all that time. I thought I was evil and flawed, and my feelings towards others hurt him a lot (he had/has low self esteem and was very jealous) so I tried to downplay it and hide it for so long... to protect his feelings.
Finally, when I realized I wasnt evil, just poly, and had some language to explain it, he ended up embracing poly and in fact, got a gf, whereas I felt I was too busy raising the kids to date. But at least we could acknowledge how I had these feelings for others, though I chose not to act on them for practical reasons, lack of time and energy.
He did continue to be jealous though, hypocritical silly man,
and that was one of the factors in our breakup 4 years ago.
3 months after we separated, I found a wonderful partner who has always been poly, and she and I have been together 3 1/2 years. I continued to date many men as well, had some interesting relationships of varying duration, and in Jan of this year found Mr Right. We are all 3 in something in between a V and a triad, with me as the hinge.