Cheating or not cheating?

[ssandra]

From another thread somebody mentioned this:

Originally Posted by James81

Yup, and I can't tell you how many men I've heard who are willing to sleep with a girl who has a boyfriend (even if they are single).

Most men think that it's wrong for them to cheat on their girlfriends, but it's rare to find a man who realizes that it's ALSO wrong to have sex with a girl who has a boyfriend.

Cheating is cheating.

and most people seemed to agree... I didn´t say anything there because I didn´t want to get off topic, but I completely disagree...

I don´t think it is wrong to sleep with / date people who are involved in a relationship. You are not cheating, they are.

I am not arguing that it is a smart thing to do, but I don´t think it is morally wrong.

I was wondering what the general opinion about this was on this forum, and for those who say it is wrong.. why is it wrong?