The Protector by K. Alex Walker

After growing up on the streets as a kid in Washington DC, former Navy SEAL, Dez vowed he would never return after joining the military. And he’d kept the promise—until the death of one of his fellow comrades forces him to go back to the city he’d been convinced was damned.
However, the night before he plans to fly out of the city, he runs into Larke Tapley, a federal prosecutor at a crossroads about leaving her secure job and branching out on her own.
The two develop a friendship, remaining in contact while he covers private missions overseas.
Over time, the need to see her in person forces Dez to do what he’d vowed never to do…
He returns home to claim the woman who’s been his rock and his reason to live for longer than she could ever have imagined.