I’m so sorry you are going through this. I know this pain oh to well. About 2 years ago my husband was having a 3 month affair with a coworker he knew for a couple of years. She was planning her wedding during the affair and the first time they had sex together was the week of her wedding! She continued to go on with her wedding and afterwards went on to her honeymoon. Her husband thought she was acting strange and he checked her phone in the middle of night when she was sleeping and saw her texting my husband sexual/love things. He found me on Facebook the next day and told me what he saw saying he thought they were having an affair. My husband when I confronted him actually admitted to everything and told me everything. Probably more than I liked because to this day it still haunts me it’s like ptsd. Her in the other hand put the blame all on my husband and lied to her new husband that it was nothing more than a kiss. It was an emotional intimate affair for 3 months. End of that story.. my husband had remorse and still loved me so he was willing to go to therapy and work on us. He realized she was manipulative and the fact she couldn’t tell her husband the truth and still married him shows she has a lot of issues with herself. We are the best we’ve ever been and even have a little baby now. I still have triggers but time will make it better. I do hope she turns around and stops seeing him and wants to work on your marriage. Her effort, remorse and love is what will make you realize if she’s worth it or not. I’m so sorry again and don’t be afraid to get professional help it really gives you a peace of mind. Please don’t settle if she’s not willing to work it out. Lots of talking and patience is what you guys need.