The Girl Who Ruled The Stars - Starlight Duology, #2

I know exactly what I am. A weapon. Tharos and his army of Shadows have infiltrated every corner of the galaxy-including my new home. They don't want war; they want our total annihilation. And if I'm not ready, the ones I love most will be the first to fall. I can't lost Xander. It would break me. But my enemies have left me no choice. I'll unleash my power and burn down every star in the sky to kill the Shadows.
The only question is: will my people still be standing in the ash of my aftermath? The epic conclusion to the Starlight duology by Heather Hildenbrand. For fans of Brandon Sanderson & Veronica Roth.