Idk if i should be happy or disappointed

Y’all these past few weeks have NOT been a win for me. This is because I have had feelings for someone for a while now and almost asked her to a school dance (I didn’t because she was going with another friend). I thought we were getting closer and closer to only find out from a mutual friend that she has a huge crush on my twin brother. They’ve been “talking” for about 2 weeks now and made it official today. I seriously thought she was giving me signs and even visited me at work. Maybe I was overthinking it but she just seemed more than friendly with me.

She’s so sweet and so beautiful though and I hope my brother makes her happy. I just don’t know if I should be happy for him and just try to get over it or let myself be disappointed for a while.