The Gallows Land — Bill Pronzini

Arizona Territory 1878...Following the death of his young wife, Roy Boone wanders aimlessly in the arid Southwest, desperate for water. Instead, he finds a heap of trouble--when he meets a pretty young woman whose face bears the signs of an abusive husband. Jennifer Todd proves kind enough to give him food and drink before he rides on-but it comes at a hell of a price....

Worried for the battered lady's safety, Roy returns to find her missing. And when two mysterious riders come within a bullet's width of killing Roy, he figure only Jennifer knows why. So Roy begins a desperate hunt for her, just a step ahead of the killers on his trail. But even if he keeps himself alive long enough to find Jennifer, she may be waiting for him at the end of a .45....