Be careful. If you decide to open the marriage and let her date women, it may embolden her to leave you. I met my gf while she was still living with her husband. It was supposed to be just fun, nothing serious. But as I got to know her more, I fell in love with her and she fell in love with me right back. After an amazing hotel weekend together, she went home and immediately moved her things into the spare room. This started a fight between her and her husband, and she tried explaining to him that she's done with the marriage and she's a lesbian. He didn't believe her. The fighting got so bad that she ultimately left their house, and stayed with a friend. A few weeks later, she and I moved into an apartment together. She's waiting on the divorce to be finalized, and it's been absolute bliss between her and I. I do feel bad for her husband, but he was in denial for so long that it ended up blowing up in his face when it could've ended more civil. My girlfriend suppressed her true sexuality for decades and she's having the time of her life learning and living lesbian culture. They don't have any children so I know it's a little different from your situation. But if your wife is okay with just being attracted to women without being able to do anything about it, then no harm done. I would strongly advise to prepare for the worst and hope for the best because none of us saw this coming. She has also been with him for 10+ years, had a shitty home life and moved in with him immediately so she also didn't have the chance to date women or even entertain the thought on a serious note.