I suspect my wife is cheating on me I saw her message on Snapchat, instgram and Facebook I need help

My (35 M) wife (35F) has been very sketchy recently. In several years ago we used to be in swingers, but then she became a teacher at a local middle school and we both agreed it needed to stop. Also, I had really started to lose interest in the lifestyle. Not sure this is even relevant, but thought I’d mention it.

Since this January, her behavior has changed. All of the normal stuff, reduced sex drive and lots of time on her phone. Plus she had a male co-worker that she frequently talked about. Apparently he’s very funny.

She was going out on Fridays after work about twice a month and not returning home until after midnight. This bothered me as I felt it was unsafe for her to be out so late. She claimed that she was fine and they just liked to hang out. I didn’t mind her going out as occasionally I did the same with my friends occasionally, but always home before midnight.

I had mentioned that I would like to go to one of these get togethers; however she said spouses haven’t attended and she would find it weird (?). I knew that was stupid as who cares and her parents could keep our kids for the night. The next week (a month ago), I just showed up anyway. She was sitting next to this male co-worker and two other teachers had the husbands with them. While I was there, Brad and my wife barely even talked. Odd given how much she would talk about him. FYI, Brad is not even attractive and he’s a teacher. I make way more than this man. i can’t understand what she sees in this guy (by comparison, I am moderately attractive while Brad is maybe a 5 out of 10. He must have an amazing personality or a huge dick. I don’t know. The whole thing rapped up around 9:30pm…not 1am. All very sketchy. At that point I was convinced something was going on.