Stage 4 breast cancer. Is there hope?

A close friend of mine has stage 4 breast cancer. 3 months ago, she was diagnosed with stage 2 breast cancer but since then it has spread to her liver and it's now considered stage 4. She's only 25 years old. I'm 24 and this is the first time I've been forced to deal with this sort of thing. I need real statistics and probabilities. Is there a decent chance that she'll survive? I'm gonna try to make the 4th of July extra special for her this year with tons of awesome illegal fireworks and everything else that makes the 4th of July memorable. I just hope that its not the last time that we can do this. If you have any experience/strength/hope to share on this, I would really appreciate it. Thank you.