When I found out about my H's EA/PA, I had the urge to go tell his boss (OW was a co-worker). I also wanted to tell OW's husband. We had gone out socially a few times together and he seemed like a nice guy. But I decided that whether I got divorced or stayed married I wanted to take the high road. Besides I knew OW had a little boy the same age as my son. Didn't want to feel I was the one who helped overturn his life.
So the night I found H and OW in a hotel together, OW kept texting H to see if I was going to "tell". I called her myself and said I was not going to tell her H a thing it was her responsibility. She wound up telling him the next day anyway. I just knew if I wanted a chance with my H I couldn't be the one to go sounding the alarm far and wide. Even though the A was HIS fault and HIS choice, I knew I would get the blame for telling OW's husband/family/etc. So I never told H's boss (although H did) and never told OW's family (although she did). I don't know if you should do it or not. If you are sure the M is over, then do what you want. But if you want to try to save the M, be careful.
Also, I DID talk to OW on several occasions before H ended the A. I really wanted to make it clear to her that me and my kids were living, breathing people whose lives were being affected by her choice to continue seeing my H. I feel bad for the other wife b/c she is having a baby and her H is having an affair. But it is up to you what you want to do. Does she deserve the truth? Yes, but maybe/maybe not from you. Good luck
