Two months ago my husband Steve confessed to me that he had an interest in seeing me with another man in bed. At first I was taken aback. “Was this just an excuse for him to sleep with other women?” I would lie in bed thinking to myself. While I wasn’t the size 6 I had been when we got married, I was still in good shape and regularly exercised at the gym. He reassured me that he had no intention of sleeping with other wom...