Saturday afternoon, wet hair

I have just had an unusually nasty fight with my sister--unusually so, because normally we don't fight at all; I just keep my mouth shut while she rages on at someone else--because she caught my mother and I discussing her latest bipolar II rage fit behind her back (guilty as charged) and shouted that whatever I wanted to say, I should stop being immature and say it to her face. So I did say it to her face: moments in her rage fit that made me angry (which I will not go into here). And then she started shouting that I must "be new here" if I haven't figured out after 21 years that this is how she's "made," and that I'm so incredibly "immature" for just not accepting it ("You're seven years older than me, and you're still so much more immature!"), and then she offered to recite a "laundry list" of my various immaturities. I have no idea what was on her list, but I was tempted to say, Let me help you out here: I'm still looking for a job, I'm still living at home, I still haven't gotten my driver's license, I haven't gone back to grad school, I'm not the sister you want me to be, and I don't have the romantic relationships that you have. Is there anything else, or is that all? All I actually said was, "Obviously I beg to differ, but I don't know how to convince you of that." And then I asked her if I could please go wash my hair so I could go out and see my friends for the first time in two months, and she told me to hurry. I'm sure that she'll add "airing a private family fight on LiveJournal" to my List of Immaturities, but I'm so angry that I have to say something to someone or I might kill her in her sleep, and I'd rather not hijack the Snarkfest Blowing Off Steam thread.