I believe that if a woman willingly has sex, and by sex I mean penetration of any kind (flesh or not) it counts as sex. It does not take a man to lose virginity.
A virgin is someone pure, someone who has not taken part in acts such as sex. And when two woman have sex, it's implied that there's been penetration. Oral sex is different, that really doesn;t count as losing one's virginity to me either, but, if a woman enters another woman (with a hand or a toy) I believe it counts as losing their virginity.
I was raped by a man, but I am a virgin. I have not had sex with another person, it doesn't matter what that person is (though I'm certain it won't be a man) if a woman 'enters' me, using a dildo or her hand, I would consider myself not a virgin.
I guess I could understand that if someone is using toys to have sex, it wouldn't seem like there's a 'connection', but if a man were to stick his 'square peg' into another girl's 'round hole' counts as losing their virginity, then if a girl does the same, it should also count as losing their virginity.