This is just a thought that has occurred to me after reading a few other threads about affairs etc.
People seem to believe that you can only ever love one man/woman at once and if you're married and having an affair with someone else you must not love your wife/husband otherwise you wouldn't be having an affair.
You can have two children and love them both. Why not two men/women?
Not that I believe love and affairs are really necessarily always one and the same. Another thing MN disagrees with. Sometimes it's just sex for both parties irrespective of husbands/wives at home. They see each other, want to shag and simply do. No more, no less. Just sex.