Artemis may have been asexual, she may have been lesbian, or she may have been neither. That, however, is not the main reason for her chastity. It is clear that she has taken that oath willingly, in order to suppress her sexual desires, and as a demonstration of feminine independence (that along with hunting). Also, when you say "By some accounts, she was Callisto's lover . . ." I ask: whose accounts? Who wrote them, and what are their titles?
As for the rest of the names you indicated, I find no instance where they are said to have been open lovers with Artemis. I recognize that the person who wrote the article seems learned in this matter, but I am very curious as to her sources. Could you please provide a direct quote proving your statements?
Furthermore, I know not whether you know what "Orthia" and "Pergaea" means. The first is simply the feminine nominative singular of ὄρθιος, meaning "high-pitched, upright" and the second simply means "of Perge". These epithets then seem not to be relevant.
(By a direct quote I mean from a primary source written in Ancient Greece or Rome, or where they still believed in the gods)
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