The difference between men and women...

is that women really believe that there is a prince on a white horse, that there is "the right someone" and only the right someone, for them.  You see, guys know that after lust there is love, and after love there is "married life".  [I put married life in quotes to include everyone in a long-term relationship.]  By the time a guy reaches "married life" he figures out that life would not be any better, in the long run, with someone else.  That's not to say that we are not attracted to, or imagine life with, someone else.  It's just that we sigh and remember our reality and know that given enough time the prospective new relationship will evolve into a Ground Hog Day repetition of the same old thing. 

Women, when they reach the "married life" point, think they chose poorly and decide they must have missed out on the right one.  Then they mistake the flirtatious friend at work, who is soooo sensitive and communicates his feelings soooo well, as being the right one.  Men have affairs because they like sex, and in general that's all they want from the affair.  Ok, maybe to feel virile at some subliminal level.  Women mistake sex for love in affairs, and this is what makes affairs so ultimately destructive for them. 

I am thinking I really put a fox amongst the geese here....