Why am I mad at myself?

So today my friend asked out a girl that I'm really interested in and she said yes. I'm feeling so disoriented because I know naturally I should be sad or angry from the fact they're dating now but I'm mad at myself because I feel so damn stupid that I thought I could ever have a chance with her. And on top of that she's dating a really good friend of mine who I'm practically bro's with, and I know that I can't do anything else but wish him the best of luck in his relationship, so I really don't know why I'm channeling all this anger at myself? Like I said I just feel like a real dumbass thinking I had a chance with her, I feel that way with every girl I like but can never go out with.