I ran across a list of books for dealing with tough issues on Little Willow's blog (which I've only just discovered). She recommends a categorized listing of books for upper high school students "dealing tough issues - eating disorders, loss and grieving, addiction, abuse, and so forth." The books are rated for both quality and content (PG-13, etc.).
Topics covered by Little Willow's list include: eating disorders, physical disorders/injuries, teenage pregnancy, teenage alcoholism, dating abuse, teacher/student relationships, parental abuse, recovery/support groups, stepfamilies, loss or physical illness of a parents, siblings or friends, and many other topics.
I think that this list could be life-changing, or even life-saving, for teens facing these sorts of issues. Reading these books will let them know that they aren't alone. And of course the books can help parents and teachers, too. It's unfortunate that books like this are necessary, but I do think that it's better to have the books available than to deny that tough issues do crop up. So, check out Little Willow's list, but hope that you won't need it.
Another book that I would add to this list, though it's written in the format of a picture book, is Annette Simon's This Book Is for All Kids, but Especially My Sister Libby. Libby Died., which is about dealing with the death of a sibling, from the perspective of a five-year-old. I reviewed this book here. It is inspirational.