Security Breach by Rebecca Deel

On the run for more than a year, Emma Tucker narrowly escapes another attempt on her life. When the U.S. Marshals fail to keep her safe, Emma turns to the most dangerous man she knows, a Navy SEAL who stole her heart before a serial killer murdered her family.
After Sheriff David Montgomery learns the woman he adores is the target of a vicious killer, he’s determined to free Emma from the threat and resume his campaign to win her heart. When they fall into the hands of the enemy, David’s skill and experience might not be enough to help them survive the killer’s trap.