Second Chance Savior by Hannah Shield

Their second chance could be their last.

River “Rubicon” Kwon has been a Navy SEAL, a CIA covert operative, and an elite hacker. The rules he lives by: Keep your heart distant. Smile, and never let them see your weakness.
There’s only one woman who broke through his barriers. One woman he can’t forget. His younger brother’s ex. When River discovers she’s the target of an assassination plot, he knows this mission could be his undoing.
Lieutenant Governor Charlotte McKinley never forgot River either. She hasn’t seen him in years when he resurfaces, claiming her life is in danger. Now on the run together, River and Charlotte race to uncover the criminal organization that’s responsible. But if River can’t bury his feelings for her, he’ll fail more than just this mission. He could jeopardize everything, including the Protectors. And lose the only woman he’s ever loved.