In the midst of all of the Jon & Kate Plus 8 brouhaha, it saddens me to think about how often people cheat on one another. (Be aware...I'm going to use "you" in my rant on cheating, but it's just a general "you" and not aimed at anyone in particular, hence the word "rant.")
My philosophy is simple: If you don't want to be with your significant other, LEAVE. Don't cheat emotionally, don't cheat mentally, and don't cheat physically, just leave. If you don't leave and you decide to cheat, you're basically taking away all of the decision making from your significant other which is almost as bad as the cheating itself. They've now been put in a position of having to be defensive, feeling like it was their fault, and dealing with the aftermath of someone who cheated. There is no more trust and obviously there was never any respect. If you respect your partner enough to tell them you love them, spend all of your free time with them, make life decisions with them, or marry them, they deserve the respect of your telling them you aren't into it anymore. This gives them the chance to choose to work on things with you or come to a mutual decision to separate. At least give them that chance.
Of course, leaving is easier said than done. I know it would be especially difficult if there were kids involved, but don't you think that kids would know what was happening? They're in tune with their parents' relationship and they know when something's amiss. It would be better to breakup than force your kids and each other to "live happily ever after" when you're all far from it.
Now on the idea of "once a cheater, always a cheater." If things weren't working in your relationship and you decided to find sex, love, and rock and roll with someone else, why wouldn't you do the same in their next relationship? How can you ever trust someone who has cheated on you or on someone else? They lack respect for the person they claim to love and are so self-centered that they feel they can do whatever they want to whomever they want for whatever reason they've justified in their own head..."oh well, they didn't pay me enough attention" or "I was meant to be with this new person - we're so much more compatible." Any way you slice and dice it, you cheated because YOU made the decision to cheat, and it has nothing to do with anyone else, how you've been "wronged" or how the new person makes you feel. You chose to be selfish and fulfill some need you had. Who's to say you won't do that again to your next "love"?
I may get flack for this posting, but nothing anyone says will make cheating ok to me. Karma will come back to bite you in the booty and you deserve it. Cheating is the lowest thing one person can do to another and it shows how little respect you have for anyone but yourself.