The Infinite Light of Dust (Brightest Stars, #3) by Anna Todd

The heart-wrenching conclusion to the epic Brightest Stars trilogy from New York Times bestselling author Anna Todd

Karina and Kael have been trying to make it work for as long as they’ve been together. The two broken souls have a lot of individual healing to do before they’ll be able to find happiness anywhere, never mind with each other.

As the world around them starts to crumble, Kael is consumed by the darkness of his PTSD, and Karina struggles to overcome her anxiety, which is at an all time high. Then someone from their past returns to invade their lives and wreak havoc on the fragile peace they’ve created. If they’re going to have the future they dream of, they’ll have to commit to fighting this battle together.