B. M. Bower 
Her Prairie Knight 

When Eastern society girl Beatrice "Trix" Lansell arrives in Montana for a visit with her brother, she is swept off her feet by the majestic, rugged beauty of the land, by the simplicity and satisfaction of ranch life, and by a handsome cowboy named Keith Cameron. But Keith seems to be immune to Trix’s charms, and as a woman used to having young men eating out of the palm of her hand, Trix is a bit put out. As a beautiful prairie summer stretches out before her, Trix is determined to experience everything life on the range has to offer. Amidst a glorious season of hard work and play, Trix finds herself falling in love with the land . . . and with Keith Cameron. Piqued by her growing attraction to him and his continued indifference, and despite the disapproval of her mother and a would-be suitor, Trix becomes determined to make Keith fall in love with her and teach him a lesson about women in the process. But Keith has plans of his own-to teach Trix a lesson about life, and what it really means to love someone . . . (Goodreads)