If you want something inspirational in line with drugs, alcohol etc. then the perfect book would be...

In My Skin by Kate Holden

Kate wrote the book herself about her teenage life on the streets. It's essentially the story of a good Melbourne girl who becomes a heroin-addicted prostitute and it leaves out all of the "boy-meets-girl" cliches. It can be a bit graphic in some parts - so depending on her age will depend on if you think it's suitable for her. But it's an inspiring read and anyone who has been there (even if it's only to a small extent) will get value out of this book.

And for fun... send her off with a copy of Stephenie Meyer's Twilight (if she hasn't already read it) .