Fight for Us by Jolie Vines

Of the two people Kit loves, one is behind bars and the other on a suicide mission. She needs to save them both.
Sharpshooter Kit never planned on joining the military, but her mom’s expensive medical care leaves her no choice but to sign up. Not that it matters. Her dream of a future with her childhood sweetheart is long over, and she’s on her own.
Until years later when she receives orders to save his life.
Green Beret Nate has Kit’s name tattooed across his skin and his soul. When he sees her face in a God-forsaken hellhole, he knows she’s walking into a trap, but damn if he can let her. Even if rescuing her destroys his best chance to avenge his murdered father.
When Nate is sent back to the US before he can carry out his self-ordered mission, Kit has no illusions. He isn’t planning on staying. Helping him return becomes her priority, though it means risking her career and her heart.
But love burns brighter than vengeance, and saying goodbye for good will be far harder this time around.