I'm in your exact situation right now. My fiance up and decides I'm not good enough for him (four more days and it would've been a year we were together), I keep getting bothered by everyone saying I don't know enough. Wisdom does not come with age, it comes from expirience. I'm only 16 and I know a lot more than what the seniors in my school know. I know right from wrong and I know what could affect my life.
I can understand where you need someone to listen. You try explaining this stuff to just anyone and they'll say "Oh it's only high school drama." Yeah, ok.
But no matter what, don't do anything drastic. Every life is worth living until it's actual end. No one will really know but you when it will turn around.