Here are some things you should never say to a lesbian:
"You just haven't met the right guy yet."
"So what's up with the WNBA?"
"You don't look gay."
"So who's the man in your relationship?"
"How do you know you're gay? Are you sure?"
"But you've been with a man, right?"
"Can I watch?" "No, really...can I watch?"
Even as i bi-sexual female I have had every one of these things said to me (aside from the wnba comment). People will always be dumb and not know when to shut the hell up, write off their stupidity and get used to it.