There's alotta good advice in this thread from Bodhi, Cav, Lasz, Vudak, Culero, etc. You're the one who know's her best, though, and this is the part where it get's tricky. You're gonna have to guage as best you can, what level's of Hard ball, or love and caring, are appropriate. All people are different; You're not completely on your own (You have your family's help in this, I'd imagine) and they are the ones who are gonna be the most help in this. Now, Women are more succeptible to attitudes against them, I.E. If everyone start's to shun her, you are gonna get a stronger reaction either way. Men are, should we say, harder shelled. Such as 3 of my (former) friends. They were outright denying that anything was wrong, even when they started to steal from family members, and were constantly broke. I moved away from the town I grew up in, and haven't seen them since. One, who was I'd played with since I was only 6 or 7, commited suicide several years ago.
I pray that you are able to help her back from the brink, JB.