No, I've never so much as looked at another girl in that way.
I really don't understand how or why anyone cheats.
I was happy in my relationship, and there was nobody else in the world but her. You could line up a string of gorgeous naked women, and I wouldn't be slightly tempted. I don't love them, I love my girlfriend. In my eyes none of them are anything compared to her, and I wouldn't for a second want anything other than her. I'm in love.
If you cheat on someone, that must mean you wanted someone else. If you want someone else, what are you doing with whoever you're with?