So my old friend does have a very lesbian vibe to her, but I never really thought... To cut a long story short, we were at a party at my house and she was nosing around in my closet. We were all just mucking around when she went into the closet, came back out and said "Hey I'm coming out of the closet!" None of us took her seriously and she went on to say "No really, this is a major moment in my life!" And although we all assumed she was joking (we were all hyper from lemonade) something about the way she said it made me wonder, why would she even bother to do that if she was straight? It was the kind of party atmosphere where you could say anything and get away with it, but still. Has anyone got any ideas?
I guess to her it was official, but the way you describe it, I don't blame you for being confused. Maybe ask her later to confirm?
She might have been doing it in a testing-the-water kind of way, so that she could take it back as a joke if she got a negative reaction. Obviously it's possible she's just joking, but it sounds like she was probably being serious.