I would want to argue that the biggest parallel in the plot structure occurs in the way that both Inman and Ada are shown to have to endure a series of challenges before they can be reunited together. Although it is Inman that has to perform the archetypal heroic quest of venturing across America to return to his beloved, both of these central characters have to confront a multitude of different challenges to reach their reunion. Both characters are radically changed as a result, showing how they have matured and grown up through their hardships, although clearly the war has transformed them both from the youthful, innocent and carefree people they once were. Note how, when they meet again, Inman describes Ada's face as being "firmer, harder" and she is dressed as a "mannish boy" in trousers. Inman is described in the following way by Ada:
He was blasted and ravaged, worn ragged and weary and thin, but he was nevertheless Inman. Hunger's seal on his brow, like a shadow over him.
Both then have suffered greatly through their separate but parallel experiences, and both have endured much to survive and to be reunited.