There comes a point in most of these abusive relationships where the victim simply wakes up to reality. Sometimes, the very realization is enough to send her away. Sometimes it takes more. There is no way to gauge what will do it. The only thing I can tell you is be patient .
Time is the only constant here.
Show her this website. Let her know that there are others, many others , who have been right where she is now. Give her my email address. All I can do is tell you that God works in mysterious way, and we all know that He only gives us what He knows we can handle. It takes a very strong woman to put up with what she's going through.