My best friend is very suicidal?

I seriously need advice for this. This is a pretty long story.. but anyways, so when we first met everything was all happy and she was fine. We've been friends for about 2 or 3 years. She met this guy through Facebook and they ended up going out. Me and his were good friends and all but I didn't really talk to him that much. He would always cheat on her, make her feel worthless.. also, her step-dad would beat her and her mom wouldn't do anything about it. Her life is pretty much horrible and I feel absolutely terrible. She moved to another city before school started this year and no one ever really talks to her anymore. When she first moved, we used to Skype all the time and talk a lot. She kept talking to her "boyfriend" but they were on and off A LOT. I was always there for her but she always treated me like her last resort and she'd go to her boyfriend for everything. They don't talk anymore and no one else talks to her. The last time any of my friends have seen her was a Halloween party. She's in a really deep depression. She recently answered my message and said "dying would be the best damn thing that ever happened to me right now". I need help, just please.. anyone with any advice just help.me.