Cheating on [M]y Gf with my [F]riend’s Mom in High School

So I'm 26 now, but this happened my senior year of high school, when I was 18.

I was a senior in high school and I was dating a sophomore who was 16. It was great, she was hot, but I've always had a fetish for older women. One of my friend's mom, Abby, was one of my friends on AIM. We were also Myspace friends but we only spoke on AIM. We chatted on AIM because I was in a band and so was Abby's son, who was my buddy, and compared notes about local gigs we played and potential recording studio possibilities. It was all pretty innocent until one night I felt bold and comfortable enough to let slip that I liked older women. She would say stuff like "I bet you get plenty of girls your age," but I would persist that I would still prefer hooking up with someone older.