Storm
The storm wasn't there when the tale began, but to Hermes, it encapsulated Orpheus and Eurydice's story. The most obvious storm was the literal one that drove Eurydice away, scattering her meager supplies to the winds and leaving her to the mercy of the cold.
But that storm, Hermes knew, was merely a symptom of the one that raged below. The ever-increasing divide between Hades and Persephone loomed like a chasm, and with their arguing the world came undone. The storm of bitter words stirred up the air above, and Hermes briefly wondered—even if Orpheus had heard him, what could he have done against the gods' wrath?
It was fittingly tragic, he thought, that the final storm that shaped their lives was metaphorical. The storm of doubt in Orpheus's heart made him look back despite everything, despite all their efforts.
Hermes could only hope that, one day, the storms above and below would calm, giving the world, the gods, and the mortals time to heal.
Maybe then their story would have a happy end.