Notorious by Janet Dailey

Eden Rossiter is the owner of a ranch in northern Nevada who is being harassed by Duke DePard, owner of the Diamond D. Her brother Vince, seems to be somewhat spineless, and wants her to sell out to Duke. Along comes cowboy, ex-rodeo, Kincade who offers to help her out. DePard's animosity results from the death of his brother, shot by Eden when they were younger. Will Eden get to keep the ranch? Is Vince really as spineless as he seems? What secret is Kincade keeping? A pretty exciting bit of a story.