The Rangeland Avenger by Max Brand

Cartwright went downstairs in the highest good humor. He had been convinced of two things in the interview with his wife: The first was that she could be induced to return to him; the second was that she loved Riley Sinclair. He did not hate her for such fickleness. He merely despised her for her lack of brains. No thinking woman could hesitate a moment between the ranches and the lumber tracts of Cartwright and the empty purse of Riley Sinclair.

As for hatred, that he concentrated on the head of Sinclair himself. He had already excellent reasons for hating the rangy cowpuncher. Those reasons were now intensified and given weight by what he had recently learned. He determined to raise a mob, but not to accomplish his wife's desires. What she had said about the weakness of jails, the strength of Sinclair, and the probability that once out he would take the trail of the rancher, appealed vigorously to his imagination. He did not dream that such a man as Sinclair would hesitate at a killing. And, loving the girl, the first thing Sinclair would do would be to remove the obstacle through the simple expedient of a well-placed bullet.