Advice?

I’m currently a senior in HS and I sort of accidentally put myself into a very difficult situation by telling my parents that I wanted to attend the prom dance. I never really did want to go but it’s one of those things where I just sort of wanted to do it because it feels like you have to.

The “difficult situation” is that my best friend/ big crush is also going to be attending which was sort of the main reason I wanted to avoid this dance in the first place. He is aware of how I feel and that he was straight blah blah blah. It was already going to be hard attending that dance without a date and literally being with the person I wanted to ask so bad but a few days ago I found out that he is going to bring a (girl ofc) date to the dance. This just made the whole situation like 10x worse and I am trying to find literally any way out of it that I can without damaging stuff with my parents (who are unaware of this situation or that I even like him at all) or with him since he will know exactly why I suddenly decided not to attend. He got mad at me once before when I backed out of plans because he was bringing a date since I apparently should have just “gotten over it” and found some other boy as if that’s easy.

Idk basically like what the world should I do in this situation to either minimize the damage or find some way to deal with going that won’t drive me insane.