-BEST ADVICE COMING TO YOU RIGHT HERE-
Bro, no bitch is worth killing yourself over. You are over-reacting, don't be a sissy. Your girl is mad at you for reacting naturally, which ended in her friend being nose-pwned. What you should do, you already did. Calling her friend and apologizing was the best you could have done in this situation.
Now, in regards to your bitch, fuck that shit man. If she really liked you, she would forgive you. But listen to me bro, the more you call her crying like a little sorry fag, the more she will distance herself from you. Also, don't use "I will kill myself" EVER while talking to anybody, you know why ? That's being passive-aggressive. You are putting the blame on others for your death, you little piece of shit. If you want to kill yourself, just do it, but don't put the blame on another persons soul.
So, what you have to do ? Hang out with your bro's, play vidya games, move on. Again, if the bitch wanted your sorry ass back, she will call you. But I feel you already messed this shit up beyond fixing. So just move on. DON'T CALL HER, DON'T APPROACH HER. Be cool, be suave. And learn from this lesson dude, once shit hits the fan, you ALWAYS need to stay cool.