How can I deal with my borderline personality, narcissistic mother?

I just read a question and the answers from someone else who has the same situation. My Mom is 82. She has been living with me and my husband for 5 years. She has been an alcoholic and prescription drug abuser all her life. Without our intervention, she would have died in her mobile home. She is now off alcohol but still takes prescription hydrocodone which is administered by me and all drugs are under lock and key. The whole time we were growing up, Mom was never available to us. When we did anything wrong, she either ignored us or flew into a rage - screaming, throwing things, sometimes speeding in the car for no reason whatsoever. She had an explosive temper. As children we were neglected and psychologically abused. Dad was never around and when he was, we got spankings for not knowing how to do things that we weren't taught to do. We lived in turmoil. Anyway, I always thought that Mom was narcissistic, but I didn't know anything about Borderline Personality Disorder until this morning when I stumbled across an article in an old Psychology Today magazine. Wow! There she was - classic. She is a miserable person. Despite the fact that my husband and I have taken care of her every need for the past 5 years, she does not trust us. She always thinks we are "mad" at her. She always needs constant reassurance that everything is "OK". She is overly nice but it comes with a price. If I bring her coffee, she says, "Thank you oh so very much." - -- If I'm too busy to respond, she DEMANDS THAT I RESPOND THAT REPEATING HER THANK YOU LOUDER, AS IF I DIDN'T HEAR HER. I dance. Once she told me, in one of her angrier moods, "I hope you die dancing -- you'll never know how hard my life is." She is obsessed with what other people think of her. She's met my friends several times. When my husband was picked up for golf one morning, Mom decided that my friends did not like her. I said, why would you think that? "Jim didn't speak to me - - - obviously they don't like me."
Her thinking is faulty. We've been though dozens of crisis periods where she's cried and agonized over why I am treating her "different". She says things like, "You and Mike would be happier if I weren't here.'" "I'm a burden to you." Blah, blah, blah. It's constant. She is an emotionally needy black hole that cannot be filled. Her mental illness is palpable in the house, even when she's silent (that's another part of her manipulation - the silent treatment. I know what's coming next --- "what have I done?" "why are you upset with me?" It's so pathetic. She doesn't care about anyone but herself. She doesn't have any money, but she spends money like water. When she first came her was was over $10,000 in credit card debt, mostly to department stores and QVC. We had to contact a bankruptcy attorney and have her file bankruptcy. Now she gets an allowance of $200 per month and she spends every penny and clothes and shoes, and jewelry that she'll never wear. Her closet is overflowing with CRAP. We're stuck. None of my other siblings will take her. She doesn't have the money for assisted living. We've decided to share in her care - 2 months off, one month on. That might work. I wish we had never taken on this responsibility. Some times I think we are going to die before she does, and we'll never be able to enjoy our retirement years. I'm going to read the books recommended her: Stop Walking on Eggshells, Recovering from the Borderline Parent, and Understanding the Borderline Mother. When I first read about the disorder, I was excited - thinking - "Finally! Something I can understand and now I can fix her and make her happy". After reading the posts on this topic, I think perhaps I will never be able to make her happy. I need counseling.