I wonder if everyone else is this way

One of my best friends is dating my recently-ex-boyfriend even though she knows that I'm totally and utterly crazy about him still and I don't know who I'm most pissed at.
Ok, there are three people I could blame for my recently aquired misery:
1) Myself. After all, I didn't have to start dating this guy in the first place.
2) Best friend. Dude. Do I even have to explain how bitchy what she did was?
3) The Boy. Damn him. He's treating her basically the exact same as he treated me. I feel like a variable.

I HATE THIS. I really kind of feel like I'm going insane. Because it's like... when I don't feel like colapsing on the ground and crying my eyes out, I either feel like laughing my ass off, or smashing a bunch of glass stuff and screaming. Or I feel like doing all three. At once. Which is weird.