Sudden Recall by Lisa Phillips

DEADLY MEMORIES 

United States Marshal Jackson Parker never forgot Sienna Cartwright–but she's forgotten him. Just like she's forgotten everything she knew before she emerged from a coma a year ago. She has no memories of her career as a spy or any idea of what the CIA wants from her. And she certainly doesn't know why she's being hunted by men with military–grade weapons. As Sienna struggles to remember who she is and who she can trust, Jackson is determined to reconnect with the woman who broke his heart while protecting the woman she's capable of becoming.