Lois Moran? Who? Well:
She had a brief affair with writer F. Scott Fitzgerald, who was married to Zelda Fitzgerald. He once remarked that she was "The most beautiful girl in Hollywood". She was also an inspiration for the character of Rosemary Hoyt in Fitzgerald's novel Tender is the Night (1934)
Really? Here's another site:
Did Fitzgerald have an affair with Moran? The point is disputed. To her dying day, Moran publicly insisted that she had not. Ernest Hemingway, who did not hesitate to peddle sometimes highly dubious stories after the death of his onetime friend Fitzgerald, implicitly supported that claim when he said Scott had never had an extramarital relationship until wife Zelda went insane.
Most Fitzgerald biographers, from what I can tell, think there was an affair, and the novelist certainly left that impression in the plot of a book that became increasingly autobiographical over the course of its creation.
Perhaps he wanted everyone to think they'd had an affair.
She married someone else, retired, and moved to AZ, where she died in 1990 at the age of 81.