Girls, Am I being selfish?

my childhood friend of 10 years dated my brother at 16. They didn’t ask how I felt about it and it put me in an bad position after it ended shortly after it started. My friend stopped talking to me and started hanging out with new people the same year. It made me very depressed to see my friend since I was 6 drop me without second thought for the rest of high school. Fast forward to 2023. I am now 23 and I have been friendly with my ex best friend for while. We have short conversations every now and then and I have forgiven her for high school since we were kids, but I never planned to be close or have her in my life again. Recently, I found out suddenly the my brother and ex friend are dating again. Once again they didn’t care about how it would effect my life or feelings at all which showed that I was never important enough in their life. It also upsets me because my brother would never let me date one of his friends and ensure they all stay far away from me. But I’m supposed to be supportive and okay with it. I will be thrown into situations where I have to be around her. Basically have a forced friendship if I don’t want to make my family look bad. Am I being selfish for not wanting to support or have anything to do with their relationship and new life together?

Girls, Am I being selfish?
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