Monsters (The Ashes Trilogy Book 3), Ilsa J. Bick - Part 3 

The Hunger Games mixes with The Walking Dead in this post-apocalyptic YA series that comes to a hair-raising conclusion in Monsters.
The Changed are on the move. The Spared are out of time. The End...is now. When her parents died, Alex thought things couldn't get much worse-until the doctors found the monster in her head. She headed into the wilderness as a good-bye, to leave everything behind. But then the end of the world happened, and Alex took the first step down a treacherous road of betrayal and terror and death. Now, with no hope of rescue-on the brink of starvation in a winter that just won't quit-she discovers a new and horrifying truth. The Change isn't over. The Changed are still evolving. And...they've had help.
With this final volume of The Ashes Trilogy, Ilsa J. Bick delivers a riveting, blockbuster finish, returning readers to a brutal, post-apocalyptic world where no one is safe and hope is in short supply. A world where, from these ashes, the monsters will rise.