Desperate Measures by Melissa Pearl

Camila has spent the last ten years trying to leave her dark past behind…but when Alex turns up on her doorstep, she’s forced to face the one person she couldn’t forget.
Growing up on the tough streets of the city taught Cam a few things, especially about love. Don’t listen to your heart, because it will always let you down. Listen to your head instead.
She’s lived by that motto as a detective with the Aspen Falls police department. Cool-headed and calm, she’s solved plenty of cases through sheer grit and determination. But when Alex, a ghost from her past, shows up in her home, her resolve falters. He’s clearly on the run and up to no good, but there’s just one problem. She loved him once…and her head can’t convince her heart that anything has changed. Especially when she realizes just how much trouble he’s in.

The last thing Alex wants to do is put Cam in danger. The woman he loved years ago, the woman he purposely left behind, deserves better. But fate has other plans. Injured and alone, he shows up on her doorstep, knowing exactly what he needs: a safe place to stay and a plan to get out from under the myriad of people who want him dead.
But he knows something else, too.

His feelings for Cam never changed. And showing up at her door could be the worst thing he’s ever done. Because, this time, he might lose her forever.