Although I see a lot of "I have a girlfriend so I wouldn't do this or that...", my practical experience has been that a lot of people cheat, especially younger people. I've found it's mostly males who cheat, but a lot of times the females know the guy has a girlfriend.
So for this thread, let's hear your experiences. Did you cheat, were you cheated on, etc..?
I'll post mine tommorow when my girlfriend isn't here