An interesting situation involving virginity...

Hi folks! This is my first post. Nice to meet you all.
On to the question.
I consider myself to be a virgin. I'm a lesbian, and I'm nineteen. I would like to lose my virginity. Now, I don't want it to be with some stranger that I'll never see again. But I'm not in a relationship, nor do I expect to be. There is one girl, well, I say girl, she's 21, that I would really like to lose my virginity to. She has a boyfriend, but I know she's had experiences with girls in the context of threesomes. She's definitely bisexual. I love this girl to bits, and I've known her since we were tiny (our mums are best friends, but they lived in a different country from us so we didn't see each other that often). She now lives around half an hour away from me. We see each other quite often, and she knows I'm a lesbian. I have a bit of a past history of abuse, and she knows about it. I would trust her with my life. My question is, if in the hypothetical scenario that her boyfriend would be fine with it, would asking her to take my virginity be a bad idea?
... I'll forever be the one who asked a bizarre question, won't I?

Cheers,
J