Found By You — Helen Conrad

The Destiny Bay Romances all take place in the same world and are loosely connected--but each story can stand on its own and each contains love scenes.

Love child--never meant to be!
Lonely Malia Carrington fell for Brad when they were teenagers.  He left Hawaii without knowing she was carrying his son.  Seventeen years later, he's back, and she's determined not to let him turn her life upside down a second time.  If he finds out the truth, she knows he will take her son away with him--along with her heart.  

From the first chapter:
Brad Connors parked the rented sedan in front of the little roadside store and looked up at the entrance. His heart was pounding. And that was pretty silly. There was nothing here but memories.
"Are you going in?" Karen asked.
He looked at his sister-in-law, startled. He'd forgotten all about her and the kids.
"Yeah, I need..."
Nothing.
He fumbled for a plausible excuse. He didn't need anything but the hunger to see Malia again was surging in him like an irresistible force of nature too strong to ignore.
She wasn't here. He knew that. Those days had been so long ago, surely she had moved on by now. Still, just the chance...
He was going in. And his heart was beating faster, even though he knew she couldn't possibly be there. She was like a dream. She couldn't possibly ever be there again, no matter how hard he tried to reach for her.
#
Malia Carrington never, ever came that way on a Friday, and when she did, she never ever stopped at Hiroshi's Store. But today she did. She needed a cool drink before she finished the drive down the coast to her beachside home.
So she headed for the driveway, parking off to the side because some tourist in a rented car had taken up the whole front parking area.
And when she looked up, her hand still on the ignition, she saw him.
He was going up the steps to the entrance, taking them two at a time, just like he always had back then. She shook her head, gasping softly. Was she dreaming?
No. It couldn't be.
Her heart stood still.
He disappeared into the store and she sat, not breathing, not thinking.
He was back.
And then she went into action, putting the car into reverse, backing out onto the highway again. It was a good thing no one was coming because she never looked. Her thoughts were a blur. She only knew she had to get out of there, drive like hell for home, and never look back.