Well, at least damaged his ego.
The green is me. The pink is the poor girlfriend.
Yesterday at 12:44am
You don't know me but, your boyfriend has been talking to me, having phone sex with me and trying to get me to come see him.
He never mentioned he was with you and when I confronted him about it, he said that it was a "complicated situation" and kept talking to me.
I felt it was my moral responsibility as a decent person to tell you just what kind of person your boyfriend really is.
I'm sorry if this causes you pain in any way, I don't mean to attack you or mess anything up and if you do decide to ignore this, just know that you deserve better than him and no one deserves to be treated this way.
I told [name] that I wouldn't say anything to you, but if I were in your shoes, I'd rather know.
Again, I'm really sorry and I only wish you the best.