A Dream to Call My Own (Brides of Gallatin County #3) by Tracie Peterson

Lacy Gallatin, the youngest of the Gallatin sisters, is a woman with a mission: to find her father's killer. Haunted by the belief that she's failed him, Lacy is also battling a desire to have something more than just revenge, something she can't quite figure out.

Enter Dave Shepard, deputy sheriff for the area. Dave has been fervently trying to find the man who killed George Gallatin, but he always feels inadequate when it comes to the beautiful Lacy. When they are together, the tension crackles between them--both when they argue and when they kiss. Lacy finds him frustratingly irresistible...but is it truly love?