Having been in both sides of infidelity I became somewhat interested in the whole subject and have done some rather indepth reading on the subject. First infidelity (here after refered to as cheating) takes place either verbally (an affair of emotion without physical contact) or sexually (no explanation required). Conservative sociologic data indicates that upwards of 70% of men and 50% of women have physical affairs within 9 years of being married. There is no good data on cheating within no-married couples nor is there any data on emotional affairs. One additional interesting data point is that women are more likely ot be able to forgive a physical affair when there was no emotional connection.("she didn't mean a thing to me, it was only sex") but men are far less likely to be able to get past physical cheating and are very unlikely to even detect an emotional affair that their wive might be having. Just food for thought.