The power struggle that occurs in the story "Roman Fever" begins some time back when Mrs. Ansley was a young and single "Ms. Grace" and Mrs. Slade was a young and engaged "Ms. Alida". Alida was engaged to a man named Delphin, but apparently he had placed his interests in Grace, instead. During a vacation in Italy, an apparent love affair flourished between Delphin and Grace of which Alida was aware. In an attempt to stop the liaison, Alida wrote a fake letter to Grace pretending that it was from Delphine, asking for a rendezvous at the Colosseum. Since no real rendezvous was planned, Alida thought that Grace's eventual jilting would make her give up on Delphin. However, something did happen for Grace became ill shortly after that incident with what was then dubbed "Roman Fever". After her time away, she returned to the public eye and married Mr. Ansley quite fast.
The story itself, however, begins in the present time. As elder widows, we find Mrs. Slade and Mrs. Ansley once again in Rome, decades after their first trip together. While Slade continues to somehow bring up past issues with the much quieter and prudent Mrs. Ansley, the women come to a dignified crossfire when they both claim Delphin's past affection. As a result, Mrs Slade confesses to Mrs. Ansley about writing the letter that was meant to move Ansley away from (the now defunct) Delphin.
Yet, Ansley gets the upper hand when she confesses that her daughter, Barbara, is actually Delphin's daughter. This is when the reader realizes that the so-called "Roman Fever" was actually Grace Ansley's time of pregnancy- which she spent away from the public eye- and apparently then was lucky enough to have found a proper husband in the late Mr. Ansley.