Die Bestimmung by Veronica Roth

In a dystopian city divided into five factions defined by single virtues, a sixteen-year-old girl leaves her family's selfless faction to join the daring faction and takes on a new identity; she soon discovers she is Divergent — resistant to simple categorization — which puts her at odds with a faction bent on seizing power through manipulation and mind-control simulations. Forced to conceal her difference while training and forming alliances, she uncovers a conspiracy that threatens the fragile social order and must confront questions of identity, loyalty, and the cost of choosing who to be.