It definitely was her mate who's put these ideas in her head for sure. It was all fine until one night she was out with said mate and I even had her mate on the phone to me "you better not mess her about" and stupid shit like that. When girls do that it usually leads to me instantly just sacking it off, because it's obvious it will lead to grief. I did tell her mate this at the time, and asked wtf she was on about, and was never really given a credible answer.
I mean if I wanted to be a cunt I would just tell the stupid slag her coke dealing bf cheats on her every week. But that would cause a whole host of even bigger problems