The reasonable conclusion people get from the Cupid and Psyche story is that it's a Roman, or least purely Apuleius' invention because it doesn't show up elsewhere in any prior sources. So I decided to do some digging.
The short answer is while it's true the story was only in The Golden Ass novel, the background and development of this is a lot more interesting and nuance.
The earliest references of the couple were figures dated to the 4th or 3rd century BC. There was a series of terracotta and statues during the Hellenistic and Roman era.
Left: Terracotta busts of Eros and Psyche embracing. Italy, Sicily, 200BC-100BC. British Museum.
Right: Eros kisses Psyche. 2nd century AD copy of a 3rd-2nd centuries BC (original). Museum of Fine Arts Budapest.
It's worth nothing that the female figure with Eros weren't named Psyche. The name was given stems from our familiarity of the story. Eros was always seen as a pubescent with wings, as well as this depictions doesn't match other identifiable characters aside from the Erotes (which for the benefit of doubt could also be them but as a singular catch for all love associates) . Dionysus and Ariadne were sometimes portrayed in this tender manner, but they don't have wings, so it's clearly not them. Another closest alternative would be Boreas and Orithyia, but Boreas was usually depicted as a grown man and their interaction is always seen as forceful as shown on Attic vases and reliefs. All of these pairs fall in the category of divine-mortal iconography with the mortal woman becoming a goddess.
Left: Terracotta statuette of Eros and Psyche. Greek, Boeotian, 4thā3rd century BCE. Met Museum.
Right: Terracotta group of Eros embracing Psyche. Myrina, late 1st BC-1st century CE. British Museum.
Psyche means "soul" in Greek, but the first attest of Psyche being used in philosophical or superstition contexts was in late seventh century BC by Thales of Miletus who wrote about stones, āhas a soul (psychÄ) because it causes movement to ironā. Plato further developed this theory by arguing the soul can even contain thoughts or reasons.
Greek-Egyptian Kinky Magic
Despite the explicit absence of this āPsycheā name, we do have her shows up in Greek magic papyri. Erotic magic and spells were the rage in Egypt that eventually spread across the Mediterranean. Magic concerning love spells mixed Greek and Egyptian practices, using the traditional Greek deities with the most popular being Aphrodite, Ares, Selene, Hecate, Eros, and even Psyche.
There were epigrams invoking Eros, Psyche, and Aphrodite. Some amulets and stones shows the characters like Eros and Psyche being bound and tortured, representing the souls under passion and lust. The similar visuals to that of the terracotta could indicate the statuettes also served as amulets.
These acts can be somewhat seen in the tale like Aphrodite torturing Psyche, Psyche burning Eros with a candle wax, Psyche put to sleep by Persephone's spell, etc. Although we don't get the definitive dates on these recipes, with some dated to at least 2nd century AD or later, they were likely reprint or copies of earlier ones. And we know that Egypt in these time were more or less obsessed with magic spells because a lot of them resembled to Egyptian sources.
-Panagiota Sarischouli's Transcultural Context in Graeco-Egyptian Magic in Rhetoric and Religion in Ancient Greece and Rome
All of this seems tangent to the Cupid and Psyche "mythography", but it's relevant because while a lot of people focus on the myth aspect, not a lot realized it was actually told within a story. Magic plays a prominent role in The Golden Ass novel. The main character Lucius was a practitioner of magic, but upon his mistake he was turned into a donkey and met many misfortunes, weird shenanigans throughout the novel. One of them has him being abducted by pirates and was about to be sold. Along with him was a girl named Charite who was distraught by her fate and an elderly woman. The latter being touched by Charite's grief, decided to tell this myth which covers two books/chapters.
In addition, Apuleius was also a practitioner and was accused of a minor crime of using witchcraft, so in some way the novel was like an autobiography-minus the whole magical realism.
So why was it written that way?
So if there's no myth of Eros and Psyche prior, why did Apuleius chooses this as a subject of the story if it's not root in myths other than the name?
Left: Terracotta statuette of Eros (god of love) and Psyche (goddess of the soul). SelƧuk, Turkey, 1st century AD. Ephesus Museum. Flickr.
Right: Statuette of Eros and Psyche with a little cupid sitting on her shoulder. 2nd centtury. B.C. National Archaeological Museum of Athens.
As of now, we don't have any records of the story before Apuleius. For unsatisfactory and boring answers, Sarischouli said parallels to the fable can be found in eastern mythic traditions like Egyptian and Mesopotamian, with Gnostic and Platonic flavor.
(Fun fact: Eros and Psyche shows up in a Gnostic text called On the Origins of the World)
Aside from the myth reflecting Greek-Egyptian magic and spells, the obvious answer would be that Eros (Love) and Psyche (Soul) is an appealing allegory, it would fit within the context of the novel. The point of the story is that despite the turbulent life Charite suffered, she, like Psyche, will find light at the end of the tunnel. This also extends to Lucius who was restored to his normal state by his savior-goddess Isis, thus joined her cult/mysteries.
Apuleius was a Platonist philosopher. Heās no doubt familiar with Platoās work as shown in his other works, specifically using Phaedrus and Symposium.
But another answer that is unnoticed is that it's suppose to resembled an ancient Greek romance novel that was popular in the 1st century AD. From its genre to writing structure, it shares the usual tropes where a couple was separated from each other and must go through hardships before they reunited. Psyche resembled heroines like Chloe and especially Callirhoe. Apuleius also shows his literary knowledge that carries into the novel. Ian Repath laid out comparison of various Greek romance novels to the myth in Apuleius and the Greek Novel: Generic Infringement.
So basically Apuleius took the story that was likely root in a fairy tale, borrowed the Eros/Psyche motifs, and repackaged them in a Greek romance writing style.
Like the heroine, Lucius went through series of turbulence in a wacky adventure, sought help from his goddess Isis, whom in his mind, was also Aphrodite/Venus, Demeter/Ceres, Hera/Juno, Persephone/Proserpina.
Faraone, C. A. (2021). The Greek and Egyptian Traditions of Breathing Stones in the Recipes of the Greek Magical Papyri. In T. Galoppin & C. Guillaume-Pey (Eds.),Ā Ce que peuvent les pierres. LiĆØge: Presses universitaires de LiĆØge. https://doi.org/10.4000/14dbx
May, R. (2023). HELLENISTIC POETRY, MAGICAL GEMS AND āTHE SWORD OF DARDANUSā IN APULEIUSā CUPID AND PSYCHE. The Classical Quarterly, 73(2), 845ā861. doi:10.1017/S0009838823000800
Sarischouli, P. (2021). Transcultural Context in Graeco-Egyptian Magic: Two Case Studies from a Bilingual Theban Handbook. Rhetoric and Religion in Ancient Greece and Rome. Trends in Classics - Supplementary Volumes 106, 106, 101ā129. https://doi.org/10.1515/9783110699623-006
Repath, I. (2026). Apuleius and the Greek Novel: Generic Infringement. In R. May & C. Conybeare (Ed.), Latin Lineages: A Family Tree from Catullus to Today (pp. 135-166). De Gruyter. https://doi.org/10.1515/9783111707419-007