Heat of the Night by Amy Knupp

Evan Drake may have had a challenging childhood, but he’s overcome it all to build a life he loves—a career as a firefighter, with lots of friends and female attention, all on a tropical island. He couldn’t ask for anything more…until Selena waltzes into his world.
Selena Jarboe was born into old money, lacking for nothing, except the one thing she aches for most—a stable, secure family. After playing by society’s “rules” her whole life, she throws them aside, walks away from her East Coast mansion, and pursues a life—and a sexy stranger—on San Amaro Island. She can’t regret the no-strings night with Evan…until she learns it has a major consequence.
With an uncertain future, Selena is sure of only one thing—that Evan is the last man who could offer her any kind of security. Evan has a lot of experience fighting for what he wants, but will it be enough to win over Selena forever?