its true and false. monster monster is right about the animal instinct.
there have been times in my life where upon meeting the right lady i would have happliy not strayed but i think the fundamental problem is that after a certain period women do not put as much emphasis on sex in a relationship especially when kids come along.
men never change always want the same level and so we end up seeking it out elsewhere
i think most men if they were getting plenty of good sex at home would not feel the need to stray but there are always exceptions where guys just have to play the field