Men Cheat.

Cheating man has deep evolutionary roots.  Biological evidence indicates that a long-term monogamous relationship is difficult for humans to achieve - not impossible, but difficult.

Infidelity is human nature. The inevitability of men’s infidelity in marriage is true across cultures. This was borne out in research conducted in rural Mexico as well as in similar studies in rural New Guinea and southeastern Nigeria. The study was conducted by Jennifer S. Hirsch, PhD, associate professor of Sociomedical Sciences at Columbia University Mailman School of Public Health. These findings are published in the June 2007 issue of the American Journal of Public Health.

Although cheating is natural, it is also natural for a woman to use her knowledge of the man's mind and instincts to keep him with her as long as she wishes.

Infidelity: Mending your marriage after an affair

How to Survive Infidelity