It depends on the situation and also how close you two are and if you both are completely honest with each other. My wife has been with her current lover for over 4 years. Her previous lovers were nice and they kept their relationships to sex only but my wife Cathy and her lover have slowly become more than just FWB, they are now very much in love. They came to me last summer and admitted to me that they are in love and asked me to decide if they should break it off, if so they would do it and not sneak around behind my back and I believed them. I thought about it then told them that I could see for many months how closer they had become, how she was always so happy, giddy and more when he was near her. I told them that I would be a fool to say no to their love for each other because in truth I found it to be so amazing to watch them, see how they embraced and kissed. He's very much a gentleman to her and so honest with me, like a good friend or bother. I asked them to be careful of their PDA's in public in our area etc but I am also happy to see them together. Our marriage is VERY strong and I know full well that she would never want to leave me. The last few weeks we've been talking about one of us renting out our home and moving in with the other and seeing how a co-habitation would work for us. We agreed that she would ...... with him for two weeks then me for two weeks. They really are a terrific couple when they are together and seeing how much love they express for each other is amazing. I haven't had intercourse with her in over 9 years so he is her only sexual partner, the only man making love to my lovely wife, which also helped to created the bond and love they now have, which again works out perfect for us. Don't be afraid of love "happening" if you have a strong bond/marriage because there's no reason that a woman can't love two men. Just an opinion from a cuckold in a very amazing relationship/marriage.