I never understood how people (especially mono guys) discuss where the line is. Like "it was only a kiss" or it was "only flirting". A friend who cheated on his wife told me "how can you be so harsh on me if you're not a fan of monogamy yourself?". Dude, that's not the point, "cheating" is just another word for "betraying someones trust"

If a guy in a strictly mono marriage goes out with another woman and hides it from the wife, that's cheating, whether there's physical intimacy or not. If a girl in a polycule hides from her partner that they had sex with someone who has an STI, that's a form of cheating. If I'm in a triad that is only open on my side (the other 2 agreed to only engage with me) then Its not cheating If I sleep around but it would be if one of them had an affair.

BECAUSE THATS WHAT WE AGREED ON. Its not that fuckin hard. You set rules/boundaries and if you transgress, thats cheating. Boundaries can be re-adjusted when circumstances change, but its always the persons choice, If they are honest with their partner or whether the choose to go behind their back.

Please don't get me wrong. I don't generally judge people, I just don't get why most don't understand that what "cheating" is defined by the people involved in the relationship., not by some social norms.

IMPORTANT EDIT:

I believe my post rubbed some people the wrong way, because I wrote it under the influence of strong emotions. I am absolutely not telling anyone what is or isn't cheating neither did I want to imply that men break boundaries more often than women or that monogamous people usually cheat or any of the sort.

My frustration comes from the fact that once again someone in a mono marriage is surprised that I don't want to date them, or that I judge them for sleeping around behind their partners back. You wouldn't believe how many mono people have kissed me during parties because "Why do you care about my husband/wife, I thought you were against monogamy"

The only thing I'm against is people who lie and deceive those closest to them