I think it would be best to assume that getting with this other man would end your marriage and then decide. It quite possibly could even if just because of the guilt you'd feel. So, I would say it is more about if you want to end your marriage or not. Then, the dating field is open to many people who could be great for you. I know the burning desire you speak of, but all relationships lose some of that over time. I had a friend go through a similar thing and almost ruined her marriage. It went a bit too far, but she never totally cheated. There was lust and new romance and she felt that new spark. Then one day, when she was sad, that man texted her and she realized it didn't make her feel better. She was looking for something to make her feel alive from someone else, when something was missing in her own life is what she decided. She also learned to tell her husband what she needed from him, like more romance. I have never been married (but in a 7 year monogamous relationship that is going well), but still hope this is helpful in some way. Consider what you want first from your marriage, then from this man. Maybe you just don't like to be monogamous which is totally fine, but be honest with yourself and break off the marriage. Best of luck!