StarPonysMama, I agree that lying is not a character defect exclusive to men. I have known a lot of female liars.

My H (soon to be X-H) is a liar. He thinks very highly of himself and is the sort who always has to be right. He doesn't like to look bad or lose face or seem less than he imagines himself to be. He is very self-centered and totally does not get that he doesn't know everything in the world or that he is not perfect. Or if he does get it, he does not want anyone to know it. So he often lies to make himself look better or if he made an error, he lies to cover it, so he won't look bad or imperfect. (My therapist has met him and says he is a narcissist.)

Anyway, that's the story of why I think one guy lies. Probably each liar has their own reason.