The Book of Ivy by Amy Engel

After a brutal nuclear war, the United States was left decimated. A small group of survivors eventually banded together, but only after more conflict over which family would govern the new nation. The Westfalls lost. Fifty years later, peace and control are maintained by marrying the daughters of the losing side to the sons of the winning group in a yearly ritual. This year, it is my turn. My name is Ivy Westfall, and my mission is simple: to kill the president’s son—my soon-to-be husband—and restore the Westfall family to power… Read more.