Anyone who has ever watched an episode of "Cheaters", "Paternity Court", or "The Maury Povich Show" AKA "You are not the father!" is aware that neither gender is exactly standing on "holy ground" when it comes to cheating. In fact many lesbians have also reported incidences of their (female) lovers cheating on them!
Gender has very little to do with why one cheats.
The goal of most cheaters is to hold onto all that is "good" in their primary relationship while addressing their other "needs" on the side.
The purpose of a lie is to manipulate the thoughts and beliefs of the listener. People lie for one of two reasons.
1. To avoid painful repercussions that will either hurt them or those they've betrayed.
2. To keep the thrill alive! They don't want anyone to pressure them to stop doing whatever it is. Secrets intensify passion/excitement.
There are no "gender shortcuts".
People are people and one has to invest the time to truly get to know the (individual) they are dealing with. There is no "one size" fits all.