My boyfriend bought tickets to sporting event and it was supposed to be bf, me, his sister, niece, his brother, and his mom. However bf’s mom can’t go and now his brother gets the extra ticket. His brother is planning to bring one of the two girls he’s seeing at the same time.

Back story of why I don’t want to go feel uncomfortable about the situation: before my bf and I even started dating bf’s brother was seeing girl 1. So she has been around since longer than the almost year bf and I have been dating. Flash forward to a couple weeks ago enter girl 2 who has been around now too. In fact bf’s brother had girl 2 spend the night and then afternoon girl 1 is over within the last week. I know bf’s brother and girl 1 aren’t dating and apparently (according to my bf) have had conversations about the fact that they aren’t dating. But I still feel icky about the whole situation and don’t want to be involved in the drama involved around that whole situation. I told my bf that I planned on telling girl 1 about girl 2 and that’s when I learned bf’s brother and girl 1 weren’t dating. So now I feel like technically he can play the field since they aren’t dating but I don’t want to be doing things like going to sporting events with both girls.

I told my boyfriend that I’m going to be uncomfortable with going to the game with either of those girls present. And he doesn’t understand why I care so much since “it’s not my business” even though he and I both think his brother is being scumy.

So what should I do?