Need advice for middle school relationship?

I've got this new boyfriend. We'll call him Alvin. When he came to meet me at my next class he ran into my other friend we'll call him Steve. Alvin and Steve have a complicated relatoinship bc they both use to date me but I broke up with both of them now Alvin's brother we;ll call him Shane told Steve I was dating them both and Steve tried to fight Alvin but Alvin's brother Shane broke up the fight and blackmailed me to brake up with both before things got worse. So Shane and I dated for a week then he broke up with me and now I'm with Alvin again. How can I cause Alvin and Steve to get along (they're cousins and I don't want to come before family)