Young people who died before reaching societal milestones of adulthood would be euphemistically married to divinities as a way of handling the grief of their lost potential. There are countless references to young people being "snatched by the nymphs," or becoming "brides of Persephone / Hades." In this passage, the Byzantine author John Tzetzes explains how the transformations of Narcissus and Hyacinthus were used to help alleviate the grief of their loved ones.
Hyacinthus Cynorti quidem erat frater venustus.
Filius Amycli autem patris, matris Diomedae,
ex terra virorum nobilium Laconum Amycleensium.
Apollo vero et Zephyrus adolescentem certatem sepe
et sane olim disco ludente Apolline cum hoc, scribant.
Vehementer cum efflasset zephyrus, discum circumvertit.
Vertice autem pulchrum cum percussisset, occidit iuvenem.
Terra autem florem eiusdem nominis reddidit pro iuvene,
quasi Narcissum miserata ob pulchritudinem.
Sed narcissi clara est allegoria.
Quia cum cecidisset in aquas iuvenis, praefocatus est.
Pulchritudinem vero extollentes, luctus solatio.
Dicunt cecidisse in aquas, umbrae suae desiderio.
Plantarum autem ficio clara, sicut et arborum omnium,
et stellarum cum ipsis atque istiusmodi.
Morientium enim affines, nutrientes desiderium horum,
ista nominarunt nominibus illorum.
Hyacinthi autem dicunt rivales, quos dixi,
ostendentes excellentem iuvenis venustatem,
quod gavisus sit Sol, oblectatus iuvene:
et ventorum flatus pro deliciis habuerint hunc.
Ut vero cum iuvene aliquo disco ludens interfectus est,
vento subvertente in verticem discum,
finxerunt quod Zephyrus invidens Soli
educit hunc e vita, atque e splendido lucifero.
--Joannes Tzetzes, Historiarum 1.241 / 1.11; Translated into Latin by Paulus Lacisius (1546) [Greek text forthcoming]
Hyacinthus was the attractive brother of Cynortus.
He was the son of Amyclus and Diomeda,
From Lacon, the noble land of the Amyclean clan.
Both Apollo and Zephyr often competed for the youth’s affection.
And—they say—once, while Apollo and Hyacinthus were practicing the discus
Zephyr sent forth a violent wind, and changed the course of the discus.
When it struck the beautiful youth in the head, it killed him.
The Earth created a flower in memory of the youth, taking his name,
Mourning his beauty the same way she mourned Narcissus.
But the allegory of Narcissus is apparent:
When the youth fell into the water, he drowned.
As a consolation for their grief,
Those who praised the youth’s beauty
Said he fell in the water, struck by longing for his own beauty.
Famous transformation tales of plants, of trees of all kinds,
And of constellation myths are similar to this.
The kin of the deceased, transforming their loss,
Name these things after their lost kin.
Just as I’ve stated, they say that the rivals of Hyacinthus [Apollo & Zephyr]
Reveal the extreme beauty of the youth,
Since the Sun reveled in the delight of Hyacinthus,
And the Wind itself also vied for his affection.
When the youth was killed while exercising with a discus,
They made up a story that the Wind, jealous of the Sun,
Took Hyacinthus away from his life—and from the Sun.