Few events cause as much turmoil in a marriage as infidelity. It can shatter trust and breed insecurity and resentment from which some relationships never recover. People who think it won't happen to them are hit that much harder when it does. Why are men unfaithful? Can infidelity be prevented? What do men say they're getting from their mistresses that they're missing at home? Do a man's friends have anything to do with his willingness to cheat?............