Behavior: Swinging - And Ducking - Singles

The first time it happened, the couple was arguing over a plate of undercooked eggs. When her boyfriend continued to complain about her culinary skills, Sue, a 32-year-old New York City artist, started to cry. "He couldn't handle it," she recalls. "He grabbed me and shoved me. I was really frightened, and I hit him with my fist." After that, their life together got worse. "His temper escalated. He'd grab my arms and hold me down, or throw things at me: tennis shoes, magazines, a book." She finally walked out, too humiliated to reveal the reason to her friends.

Sue's experience...