Remember the dictum about never asking a woman for advice about women? This answer from Dear Prudence to a man who belatedly found out about his wife's sexual past is exhibit A.Your wife violated two rules: One, she didn’t tell you when she should have told you. Two, when she told you, she told you too much.But you now need to put what you’ve learned into perspective. You two have been together for five years, and you don’t indicate that during that time you have ever had cause to doubt your wife’s fidelity or her satisfaction with your sex life. I don’t know if meeting you was the turning point in her life, or if by the time she met you she had moved past her emotional problems and was ready for a more fulfilling relationship. Whatever it was, it’s clear that when you got together she was...