Once in bed at night, Cathy's boyfriend would almost instantly curl up in the fetal position facing away from her and begin breathing heavily as though asleep. "But if I put my arm around him, he would stiffen up and hold his breath," she says. "A couple times, I even saw him hurriedly shut his eyes." Sometimes the 37-year-old from St. Louis, Mo., would take a more direct approach, telling him, "I want to be with you" -- but she often ended up being rebuffed. It wasn't uncommon for him to ask, "Why do we have to have sex all the time?"