Mother Issues

My mother keeps acting like it's going to be so much work being the grandmother of triplets, but to be completely honest, I don't really want her too involved with them. I'm starting to get over the fact that I ended up moving out when I was 16 because she decided it was no longer worth it to feed me (Still slightly bitter), but any time I'm around her I feel nothing but negativity. She managed to make me insecure about things I never used to care about, like constantly telling me when I'm breaking out and trying to pick at my face, or trying to convince me that I need to lose weight when I'm 135lbs and look great. She complains and gossips about things going on in our family that are none of her business. Probably the thing that bothers me the most is the way she treats my brother. My brother did a lot of drugs when he was younger (namely meth) and since then he has developed some serious psycological issues, to the point where he thinks the Russian mafia is after him and he is a danger to himself and others. My mother, who is probably the only person who would be able to convince him to get help, pretends that none of this is happening because she likes to pretend we're all one perfect family. On top of that her house is constantly a mess, and her dogs have mange. The only reason I haven't called the humane society and had them take the animals it because my childhood dog, who is an absolute sweetie and would never hurt anyone, is half black lab half pitbull and would most likely be put down, and one of her other dogs, also a complete sweetheart, is deaf and old and would also probably be put down. I don't want my children around there, and if I could I would adopt my 10 year old sister just to get her out of that poisonous environment. Is that wrong of me?