The Unsung Hero by Suzanne Brockmann

After a near-fatal head injury, navy SEAL lieutenant Tom Paoletti catches a terrifying glimpse of an international terrorist in his New England hometown. When he calls for help, the navy dismisses the danger as injury-induced imaginings. In a desperate, last-ditch effort to prevent disaster, Tom creates his own makeshift counterterrorist team, assembling his most loyal officers, two elderly war veterans, a couple of misfit teenagers, and Dr. Kelly Ashton-the sweet “girl next door” who has grown into a remarkable woman. The town’s infamous bad boy, Tom has always longed for Kelly. Now he has one final chance for happiness, one last chance to win her heart, and one desperate chance to save the day…