“Cheaters do not advertise their cheating and are very private about it, so it is always hard to prove it. Most of the time it is happening under the guise of a friend, a friend visiting town, friends from the past, neighborhood friends, vacations with friends, shopping trips, long walks alone, time spent at the gym, coworkers, faking going to work on sick, comp time, or vacation days, company overtime, company emergency, company conferences, and so on.”