I would imagine that if a woman was asked if she was a lesbian, and she wasn't, the implication that she simply was so bad at sex that she MUST be a lesbian, would make her run off crying. It's a pretty devastating criticism, if you ask me, whether justified or not. Maybe she thinks the sex is pretty good. To hear that it's so bad to you that you think she doesn't even like men obviously hit a nerve, but probably not the one you think.