"and I begged her every day for the month I knew to let me say something. It is her sister, so I honored her wishes."

Then to the ex GF privately, "Lose my number, I am done hearing anything coming out of your mouth. You are a lying whore, just like your sister. Sooner or later you would cheat on me, and I can't be with someone like that."

Dude, you are sort of doing something about it now, though I don't know what the odds of this getting back to any of the involved parties. Keep in mind that if you are standing next to a fan, and shit hits it, you are getting some on you.