A Court of Mist and Fury by Sarah J. Maas
Synopsis from GoodReads:
Feyre survived Amarantha’s clutches to return to the Spring Court—but at a steep cost. Though she now has the powers of the High Fae, her heart remains human, and it can’t forget the terrible deeds she performed to save Tamlin’s people.
Nor has Feyre forgotten her bargain with Rhysand, High Lord of the feared Night Court. As Feyre navigates its dark web of politics, passion, and dazzling power, a greater evil looms—and she might be key to stopping it. But only if she can harness her harrowing gifts, heal her fractured soul, and decide how she wishes to shape her future—and the future of a world cleaved in two.