Being confrontational - friend with my ex

Date: 7/31/2019

I’ve known for about a week now that my ex girlfriend stays over into my shift mostly just to flirt with the techs at our job. Her cheating on me is the reason we broke up. I heard that her and someone I was friends with have been flirting a lot recently, and it’s bothered me. Last night, I dreamt that I confronted him about it. I vaguely remember it. I think I tried to play coy and just said something like “F*** her yet?” and I believe I got my answer which was a “yes” but I don’t recall much after that.