Gorgeous women falling head over heels for a not-so-cute guy may seem unrealistic—just consider Kevin James and Amber Valletta in Hitch. But relationships where one is the Beauty and other the Beast tend to thrive best. One study published in the Journal of Family Psychology suggests that relationships where the man is less attractive than the woman are happier and more emotionally satisfying. The reason: Those husbands are more committed and invested in pleasing their wives because they felt a beautiful wife was a "good deal."