Well I guess techinically I'm not cheating since I'm not technically committed.
Actually now that I think about it I only really cheated on 1 of my girlfriends. Well 2 but one was a witness to a crime and I needed her to testify for me so that relationship doesn't really count.
It was my only long relationship (2 years) and I cheated on her 3 times.
1) I got drunk and let this chick blow me while I was driving.
2) I got drunk and let my sister's friend blow me.
3) I wasn't drunk, the relationship was nearly over, and I let the door girl where I work blow me.
I felt really guilty after the first 2 times, by the 3rd time all the guilt had burned away and I suffered an alignment change to neutral evil.