Cassandra was given the gift of uttering true prophecies, but was cursed so that they would never be believed. Commonly, Cassandra incurred Apollo’s wrath by refusing him sexual favours after promising herself to him in exchange for the gift of prophecy.[15] In Aeschylus’ Agamemnon, she bemoans her relationship with the god:

Apollo, Apollo! God of all ways, but only Death’s to me, Once and again, O thou, Destroyer named, Thou hast destroyed me, thou, my love of old!

And she acknowledges her fault:

I consented [marriage] to Loxias [Apollo] but broke my word. … Ever since that fault I could persuade no one of anything.[16]

Latin author Hyginus writes in his Fabulae:[17]

Cassandra, daughter of the king and queen, in the temple of Apollo, exhausted from practicing, is said to have fallen asleep; whom, when Apollo wished to embrace her, she did not afford the opportunity of her body. On account of which thing, when she prophesied true things, she was not believed.

However, other versions of the story have been given; Tzetzes wrote that Cassandra and her brother Helenus received their gifts of prophecy after being left overnight in the temple of Apollo, and in the morning they were found with serpents licking their ears.[18] Additionally, Euripides wrote that Apollo left Cassandra to be a virgin, and the god was angered when Agamemnon took her as a concubine.[19]

Her cursed gift became an endless pain and frustration to her. She was seen as a liar and a madwoman by her family and by the Trojan people. Because of this, her father, Priam, had locked her away in a chamber and guarded her like the madwoman she was believed to be.[20] Though Cassandra made many predictions that went unheeded, the one prophecy that was believed was that of Paris being her abandoned brother.[21]

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Oh fabulous. She was cursed to never be believed because she dared to say no to having sex with Apollo.

The fact that women are often questioned and not believed in this way shows this myth has not lost it’s reasons for existing.