Eclipse (Book 3, The Twilight Saga)
By Stephenie Meyer
This novel, the third in the series, picks up right where New Moon left off. Bella and her vampire boyfriend, Edward, are preparing to graduate from high school. Meanwhile, Bella manages to reestablish her friendship with werewolf Jacob Black. This leads to numerous awkward situations between Edward and Jacob, but Bella is the one who suffers the most, as she finally realises that there's much more to her relationship with Jacob than she initially thought.
While all this is going on, danger looms on the horizon. Seattle has been plagued by a series of violent homicides, and it soon becomes apparent that the killings are not the work of the average serial killer. It turns out that these mysterious deaths are connected to Bella, who's also busy worrying about the fact that Victoria and the Volturi have it out for her, too. On top of all that, there's the small matter of Bella desperately wanting to become a vampire herself, but no one (including Bella herself) is sure if she can handle it.
Tegan, my daughter, wanted me to pick a side between Edward and Jacob. I still like Jacob better. I just don't understand why Bella loves Edward so much; Jacob is a far better catch and who she probably would have ended up with if it wasn't for the Cullens.