Final answer:
The question seems related to potential infidelity by a character named Stanley in English literature, possibly in a work related to F. Scott Fitzgerald. However, without more context, it is not possible to provide a definitive answer regarding Stanley's actions.
Step-by-step explanation:
The question you're asking about Stanley cheating on his wife and Cynthia seems to be tied to a literary subject, possibly related to a novel or a character study within English literature. However, without specific details about the text or the author in question, it's not possible to provide an accurate answer.
It is worth noting that you've mentioned Fitzgerald and his wife Zelda, which could suggest that the question might be about a character from one of F. Scott Fitzgerald's novels. In his works, themes of love, infidelity, and the high life during the Roaring Twenties are common. If Stanley is a character from a Fitzgerald novel, he could embody some of these themes, reflecting on Fitzgerald's own turbulent life with his wife Zelda and the era's notorious lifestyle.