Twilight by Stephenie Meyer
For more supernatural romance:
Daughter of Smoke and Bone by Laini Taylor for a heroine who stands her own.
The Goddess Test by Aimee Carter for a modern take on the Persephone myth.
Secret Lives by Gabriella Poole for the story of a new girl at a guarded school full of secrets.
Finding Sky by Joss Stirling for a heroine learning to embrace her power.