Very interesting, English, that you went with your mother to Alice in Wonderland. I was hearing about Lewis Carroll's comment on the story lately ... he said it was about "malice." I have also heard people call dealing with narcissists as "going back down the rabbit hole" (as in Alice in Wonderland) or "going back to Oz" (as in the Wizard of Oz). I think that this is why the first Disney Alice in Wonderland was a total box-office flop ... because they tried to make a cutesy Disney film out of a story about ... malice.
In my opinion, you will just have to take this detaching from your mother thing one step at a time ... one foot in front of the other. One of the things we have all realized her on this board is that we can't MAKE the Ns in our lives stop trying to squelch our voices. We have to instead ... I guess maybe "stop caring about what they do" so much. In some way we have to stop letting everything they do affect us. And it sounds like your practical situation, as well as your emotional situation, requires that that be a step-by-step process. One foot in front of the other.
Michael Mahoney, whose work I admire greatly, wrote a book called Human Change Processes. He explains that, as we unpeel "layers of the onion" (as someone else has recently written here), we eventually get down to "core ordering processes" --- the ways we have of making meaning in our lives and in this world. Often these core ordering processes are what are making us so miserable --- we organize our world around what our parents' values are/were, what they will say about us (or what they would say about us if they were still alive), around jumping through hoops to make an un-pleasable person happy. However, changing these core ordering processes feels like death to self ... facing changing these things is such a painful process THAT IT IS NECESSARILY SLOW. THere is a WISDOM in the slowness of the process of change. So I hope that you will give yourself room to breathe, room to SLOWLY make the changes you want to make, room to move.
The people that want you to be a healthy, happy, whole person --- that includes us on the board and I expect people in your 3D life as well --- don't demand quick and 180 degree changes ... it's OK to change at your own pace. What's important is that you now see soooo clearly what is making you unhappy, and that clarity will impel you to change, there is no question that the change is going to happen.
Maybe you're wondering why I'm focusing on inner change when you feel so stuck in your practical, material, day-to-day circumstances of living in a small town where your mother has some power (maybe a lot of power) to make life difficult for you. I think that as the inner work is done, it will become easier to tolerate the monkey-wrenches she can throw into your day-to-day life, in order to be free of her constant abuse. You will become more resilient and able to tolerate the stress of whatever she is able to do ... and truthfully, I suspect that you will find that other people in your community ALREADY KNOW HER for what she is.