The Angel and the Agent by Vanessa Gray Bartal

Ethan Allen is the job, so much that not even his friends know his real name. A Navy SEAL turned secret agent, he specializes in getting in and out of countries unseen. As far as the US government is concerned, he doesn’t even exist; he’s a ghost. For Ethan, the job bleeds into his personal life. He never gets attached, never gets involved. Enter Amelia Eldridge.
At twenty two, innocent and inexperienced, Amelia should be easy to resist. But from the moment they meet, she challenges Ethan at every turn, worming her way into his heart. When Amelia gets caught up in international intrigue, Ethan is the only one who can get her back out. But can he do it without losing the one thing he fears losing the most–his heart?