WHY WE CHEAT By SUSAN EDELMAN -------------------------------------------------------------------------------- FORBIDDEN PLEASURES: Some researchers believe changes in gender roles are prompting more married women to sleep around. July 13, 2003 -- More women are cheating on their husbands - and doing it without remorse, sex researchers say. A stunning 90 percent of adulterous wives told one Manhattan researcher they suffered "no guilt," but rather felt "entitled" to the pleasure and excitement of their secret trysts, said Susan Shapiro Barash, a gender-studies professor and author. "Women feel entitled because they're not getting what they need in the marriage. That's why women today have affairs,"...