At the Rainbow's End — Susan Aylworth

When Meg Taylor returns home to Rainbow Rock, Arizona, she never expects that Little Jimmy McAllister, the son of a pig farmer, would have become Prince Charming. Nevertheless, Meg intends to stay for only a short while. Their differences are too great to be overcome. His home is the high desert; hers is the crowded city. Intentions notwithstanding, Meg soon discovers that plans made in the clear light of day fade as suddenly as a rainbow when confronted with the beauty of a Painted Desert moon.