Actually, there is an average, because sexual encounters are a measurable thing. But there isn't a 'normal', which is what I think the last two responses are referring to. But I'll stick with 'averages': And you can't talk about average without putting it in context. Are we talking ANY woman, including single women? Or just married ones? Or with a boyfriend?
I was going to post that the 'average married couple' (based on tons of stats I've read) has sex 2-3 times per week. But since that's not your situation, your gf might be talking about a totally different scenario. I don't know of any stats for single women, or all women.
(btw, the funniest survey results I ever read were when a large number of married couples were interviewed and according to the men, they all had sex with their wives about one more time per week than the wives had sex with them. Take that for whatever it's worth

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