Sparks Like Stars by Nadia Hashimi

https://www.goodreads.com/book/show/53746807-sparks-like-stars

Kabul, 1978: The daughter of a prominent family, Sitara Zamani lives a privileged life in Afghanistan’s thriving cosmopolitan capital. The 1970s are a time of remarkable promise under the leadership of people like Sardar Daoud, Afghanistan’s progressive president, and Sitara’s beloved father, his right-hand man. But the ten-year-old Sitara’s world is shattered when communists stage a coup, assassinating the president and Sitara’s entire family. Only she survives.

Smuggled out of the palace by a guard named Shair, Sitara finds her way to the home of a female American diplomat, who adopts her and raises her in America. In her new country, Sitara takes on a new name—Aryana Shepherd—and throws herself into her studies, eventually becoming a renowned surgeon.

New York, 2008: Thirty years after that fatal night in Kabul, Aryana’s world is rocked again when an elderly patient appears in her examination room—a man she never expected to see again. It is Shair, the soldier who saved her, yet may have murdered her entire family. Seeing him awakens Aryana’s fury and desire for answers—and, perhaps, revenge.