Is it too late to try to repair things with my 86 year old mother?

First let me say I'm no prize myself! I'm a 54 year old mother of two young teens. I moved in with my mother and kids after a bad divorce that financially ruined me and I can never recover from so, here I stay. Our relationship is TOXIC and I've been in therapy for many years due to deep depression. Since I moved back 8 years ago I've been having BIG mother issues. As a child my mother smothered me and made all my decisions (not my choice). She has high anxiety and has always told me everything is too dangerous! So resentment sent me down that exact road. As far as my childhood goes it was good and I honestly believe two things for sure if I didn't live with her our relationship would be much better and that if she hadn't continued certain behaviors I would be okay. These are things I've been asking her for a minimum of 6 years and she just ignores me or rolls her eyes and says I'm too sensitive. Yes mom I'm your sensitive daughter and if you know that about me why don't you treat me that way instead of making me feel damaged. I told her once she was insensitive and she said "no I'm not". My biggest issue is she treats me like a child and will not stop! She also treated my kids like they're hers and constantly tells us all what we should or shouldn't do yet ignores any advice herself. She's a great ignorer. That's her go to when I'm a bad girl. She is so controlling and manipulative and my sister's only see a little of her worst and admit shes sneeky and incredibly stubborn. She saves most of her overbearing and hurtful stuff for me, the youngest so 3 of 4 of my siblings don't see why I'm so angry at her. One of my brother's felt the same way that mom treat us like idiot kids. That same brother is now in a nursing home (at 64 years old) and is mostly clear headed. Once I took my mom to visit him and I'll never go with her again. She patted him on the head and bent over to talk to him like he's brain dead. I wanted to kill her! Why doesn't she know we have anger at her for treating us like kids? I've told her how much it infuriates and insults me when she does that a million times! I've been trying to get her to understand that I want to be treated like the adult I am and she'll say " once a mother always a mother". I get it but it's a parents responsibility to mature with their children. A toddler doesn't need as much care as a newborn and so on. In her head I never grew up and she encouraged me to be dependent on her. Also she judges me by what was acceptable in her day 1950's.. My sister's let her do whatever she wants because they say she can't change now. People can change and these are issues I've been experiencing with her for a long time. Couldn't she have changed a few things especially due to us fighting. I really know that no one sees what I see and feel. Also the fact that my mother denies or ignores whatever she wants and rolls her eyes or ignores me and tells me im too sensitive. I've really been questioning my own sanity. Am I imagining all this pain or is it there? And that really scares me. Did I make all this up? She once told me its all in my head. So do I forget all this ( which obviously I can't) and suck it up and then feel terrible for the rest of my life once my mom dies or do I have a right to express anger and hurt or feel guilty for telling her these things at her age. I just want to reiterate I've been asking her to back off for about 6 years now. Please advise. This is consuming me and I hate it. Thank you all for listening.