Relentless Series by Karen Lynch
Now at seventeen, she is still haunted by memories of that day and driven by the need to understand why it happened. Sara has always been fiercely independent but in order to survive now she must open herself to others, to reveal her deepest secrets. And she must learn to trust the one person capable of breaking down the walls around her. To keep the people she loved safe, Sara left everything she knew behind. She soon learns this new world is nothing like her old one, and she struggles to make a place for herself among the Mohiri. But it soon becomes apparent to Sara and to everyone one around her that she is not your typical warrior.