My wife is having her second affair with a married man in two months. She's away with him this week at a band camp and I want to expose them but know that it will appear that I am controlling which is an issue with us. She states that it's part of her gradual breaking away from me. Over the last few years she's become increasingly angry, impatient, has a low frustration tolerance and is struggling to find happiness. Both her siblings and her father are bipolar and she's refusing to seek any treatment even though the symptoms are there. I have spoken to a psychiatrist 4 times now trying to get help who assured me that I have done all that I can and that she will seek help in her own time.
Unfortunately the Psych is correct. Just like everything else, only the person with the problem is the one who can do the fixing. My H is an admitted alcoholic, but he is too "Scared" to do anything about it.
IMO, you shouldn't stand for an outright affair with another married man. I'm not good at taking my own advice, but you have to put your foot down here sometime. If she can go off to Band Camp with someone she is commiting adultery with, I'd tell her to take her instruments right over to his place.
On a silly note, I have to say I giggled when I saw that she went to band camp. Totally reminds me of the movie American Pie. Not trying to make light of your situation, but it just strikes me as funny.
Good Luck to you. Maybe if you try to maintain some sort of boundary with her and her affairs, she will wake up and see the light.