I fell in love with my best friend

I (33m) feel terrible about all of it due to all the specific details involved. I met her(30f) three years ago, at my now ex wife’s(31f) work event. We had an immediate connection and spark. But we have never acted on it. We’ve both talked about our mutual feelings. She is married and has been for over ten years with children.

She is an absolutely amazing woman. She takes care of her home stuff(kids, cleaning, cooking, paying bills), works and makes her own money, and just has an amazing drive to always try to do and be better.

The last year for her marriage has been rough with a lot of strain on it and bumps in the road. Her husband(29m) has recently asked for a divorce, has been ignoring her, stating not to bother him unless it’s about the kids, and is dead set on divorce. His request for divorce is unrelated to anything to do with me and just their disagreements and financial situations.

I have been fully supportive of her in trying to work on saving her marriage. Giving advice on how to work on things with him, all that stuff. Recommending on what to say to him and how to handle the situation. I’ve stayed as neutral as possible through this. The thing that makes me feel absolutely terrible though is that deep down I really hope he follows through but I know that isn’t what is best for their family.

The last kicker is that she is best friends with my ex wife which we (the woman I love and myself) have discussed the potential problems on that situation too.