UPDATE: We had a conversation, it went fine, except A absolutely went off on our housemate who wasn't there and said she (M) had no right to say anything to her about V because M doesn't pull her weight around the house. I messaged M after the conversation saying it was sorted but warning her that A was mad at her, thinking I was implying that she should tread carefully. She didn't. A knows I said this, and without saying a single word to me, has decided it was a case of me bitching about her rather than trying to keep the peace, and isn't talking to me. She went on a huge screaming rant about me to R (and then told R not to tell me - I guess only she's allowed to talk behind other people's backs?) about how I'm crazy, the fact that I'm "weird" (custom coloured hair, queer, don't mind being counter cultural) somehow being relevant to this, and that I "pretend to be disabled" (I'm diagnosed with fibromyalgia but I've never used it as an ~excuse~ to not pull my weight - I just swap chores that cause me pain for different chores etc). She's also set on moving out now, apparently. She's said this before but I really hope she's telling the truth this time, because I'm done until I get an apology for this crap (which I doubt will happen).