Prairs are important (and I am praying), but it is really important that she gets herself help,as well. Does her family know she is doing this to herself? It may seem hard, but the most important thing is being there to support your friend. You will never be able to solve her problem (I'm sure you know that, though.), and neither will she till she is ready.
I do hope that your friend will be o.k. Try to stay by her side during this rough time. I know it may be difficult, but I lost a lot of friends when I was anorexic, and it was a horrible feeling. It is wonderful that you are trying to help her.