@itsmYarD That is not strictly true, I would say the numbers are pretty similar to be honest, the only difference being men usually give themselves away far easier than women do. Women find it easier at keeping secrets, keeping up a pretense etc than men do.
@Mindy Couldn't agree with you more, men whine when women cheat, do as Mindy said, get yourself into an open relationship, do what you want.
@Topic I wouldn't leave her, I wouldn't slap her either, it would depend entirely on the circumstances. For example, if it was with another woman, guaranteed forgiveness :P if it was with a man, I don't know, depends what our arrangement was really. Oh, and I wouldn't cheat back, because if she has cheated on you, it means she obviously doesn't give a crap about you, so why would you be hurting her or whatever by doing the same to her? lol Makes no sense.