I normally can't handle dark books, but I really love Sabriel.
Sabriel is able to walk in death and bind undead things that manage to make it back into the world of the living. She calmly handles the scary and impossible things happening in her kingdom, even though she feels ill-prepared and as though her father should be the one handling the situation.
I really can't do it justice. It's one of those books that has made it into the category of books that I will reread.