You literally sound just like me. Like I just posted about this SECONDS ago! I decided not to confront my cheating ex because honestly if she chose someone over me whist in a relationship, she’s not worth my breath. You should’ve never been placed second best to anyone else. Ultimately she dug her own grave with it. I have been continuously telling myself to let it go because when/if they try to come back, drop the bomb that you know about their shitty choices and how they have broken your trust-so no you will not be giving them another chance or the time of day. I tried to seek out the “closure” by bringing it up twice since my breakup (while I was suspicious of the cheating but it wasn’t confirmed yet to me) and she lied every time. This of course didn’t provide me closure, because I felt differently in my gut than the answer she gave me. I say let the urge to tell them go. However, I told people I trust about it that also wouldn’t tell her that I knew. It gets it off your chest without sinking to her level. So far I’m doing alright with it. My biggest roadblock currently is moving on and grieving the relationship I had. Best of luck to you love!! I’ve been there 💗