Hi Jan, I'm not sure when you say "another" whether you mean a man or a woman? My W began an affair with another woman for all the usual reasons anyone starts an affair. I knew about it for sure about a year before I ended the marriage. She had been complaining about me for years before that (I didn't know she was involved with someone else at the time) and I tried to address the issues e.g. you're not romantic enough, you don't listen well, you don't help plan weekend activities etc. No matter what I did, it made no difference. I discovered DBing and it saved me. It helped me take a different approach when this wasn't working. It helped me become a fuller more attractive person and was key in me successfully moving on.I also became a person of Christian faith which was an incredible support during this difficult period (and still is!). Finally, when I couldn't deal with it anymore I gave her an ultimatum, to give up the OP or our marriage was over. She chose to end it. We now successfully co-parent and have a fairly good relationship. Am I anywhere close to addressing your situation?