HELP!!

What the hell am I supposed to do? I just told my friend that I was going to move away after I promised her I wouldn't. My parents live separate and my friend is battling severe depression. She said she was going to kill herself if I left. I feel like I don't deserve to be her friend anymore. I hate this. I've been crying for the past half hour. She won't text me back and I feel like it's already too late. It's all my fault if she's dead! Should I stay with her or should I go live with my dad so I can get better schooling, jobs, opportunities, and bacically better life? I live in Reed Point MT and there is absolutely nothing to do here. I don't know what to do.