My (16F) best friend (16F) really wants her boyfriend to join us in the school musical next school year. i would be totally okay with that, if it wasn't for one thing. he's my ex. also, if we ended on good terms, i wouldn't mind either. however, we broke up on horrible terms and haven't even made eye contact since. i was --i guess-- okay with my best friend dating him (though there is some drama there since they were in the talking stage behind my back for a month), as long as i didn't have to be around him. however, the musical is my life and there's no way i'm not doing it, and i just feel like he's stepping into my territory. if he joins, it won't only be awkward for us, but she'll also probably have to pick between us and i don't want to put her in that situation. i explained all of this to her so that we can work it out before it turns into a huge mess and she said it's her boyfriend and they're gonna do what they want and basically got really mad at me. AITAH?

one more thing. she claimed that i was telling her not to support her boyfriend. that is not at all what i'm saying. i'm suggesting that she talk to him about it and if he still really wants to do it, then we can figure out what to do from there.