You thought a fling would spice up your marriage.Now she is deeply, madly in love with him.To her, he is everything you are not.
You and your wife have been married for almost thirty years (you had been high school sweethearts and got married quite young, before either of you had finished college). You had been the only mad she had ever had sex with -- until she started cuckolding you about six years ago, and now she is very open about dating and having sex with other men. She made it clear that this was just something she wanted and needed to do, but that if she ever found out that you had cheated on her that she would divorce you -- so now this has simply become the way your marriage is.