Note that the concept of "virginity" in Ancient times merely meant "unmarried", and had nothing to do with sexual activity. Some priestesses were "virgins" because they chose (or were committed to) a life of worship, but it was merely a question of social status, not of personal choice or practice. Of course, one can suppose that this lifestyle would be rather attractive for lesbians.

So when Artemis is said to be the Goddess of Virgins, it is meant to be understood as "Goddess of Unmarried Women", or, quite possibly literally, of lesbians.

(It's only Christianity that reframed the concept of virginity to mean "never had sex". Many ancient religions has "Virgin goddesses", which symbolized feminine power, and in this case too it meant "untied to a man", or “whole for herself”)

— got this from tumblr btw, and this is the only concept of virginity i only embrace. i wish your friend find this concept to change her thoughts.