My Impossible Resident

I work in a LTC facility as a CNA. My assignment is a very difficult one, and one of my residents is totally impossible to take care of and make content. She is a 47 year old woman who has always been overweight. Her height is barely 5 foot, and she is 365 pounds. When she first came in a year ago, I was warned that she had fell on an aide in a previous facility and paralized her from the waist down. I was also warned that she was a very mean woman, combative, and abusive. But, I was determined to make friends with her and make her as comfortable as possible while we work on losing enough weight for her to have therapy and walk again. Her parents are her POA, and they have always treated her like a toddler. She is on a strict diet to help her lose weight, but whatever she can't have, she wants. She is constantly screaming and swearing at the top of her lungs because she constantly wants something that the doctor doesn't allow her to have, or she wants the maintenance man, or the dietician, or the administrator, or the case worker, or the nurse, or the bookkeeper, etc. She runs me ragged every day, and we have all documented in her behavior log, but the administration wont do anything about it. Personally, I think she needs some long-term psychiatric help, and some really tuff counseling, but who listens to the puney CNA? Of course she has CHF, and her blood gases are too high so she feels like she can't breathe all the time. Her main focus on life is food, food, food, but then she is extremely fearful of dying. I've tried so hard to be her friend, but she always screams at me for everything and nothing at all. I use to be up to the challenge every day going to work, but the past month or so I have gotten to dislike this woman very much. I don't want to give up on her because I get the feeling that she is expecting me to, but I need some suggestions on ways to approach her tantrums, deal with her insults and screaming, and try to maybe boost her level of self-respect. I mean, I know she is miserable, and I just want better things for her than laying in that bed, peeing and pooping all over herself, and refusing to even brush her teeth or get up to have a shower. Thank you. I feel better, kinda.....