My Mom is miserable and is determined to make me miserable.

My dad & brother died 2005. Mom lived w/me & husband for 7yrs. She became a drug addict & was stealing my meds (I have spinal cord disease) & attacking me physically or fighting me every single day. I have sat up nights on end because she threatened suicide. She was put in hospital w/phenomena & a system so full of drugs the drs said she should be dead. It left damage to the brain & is in early stage of dementia. She refused any help w/drugs and made my life hell so I put her out. Forward 2 yrs, she has a trailor & my brother and family live with her. She can't live alone since she says she'll kill herself. When she gets sick (which is often) she goes outa her head. My brother & I want to help her but she refuses any of it. This is what she wants...us to be stuck to her side every second, jump at anything (no matter how crazy) she wants done, to listen to her constant life of misery, let her be free to attack anybody she chooses. She is jealous of our spouses cause they want some of our attention. She says we don't want her so if left alone she will kill herself to get some peace. I've offered to go to therapy w/her but no go. She don't wanta do nothing nor go no where or meet anybody for friends but says she miserable. I thought making her move would help my sanity but now I just spend my time on the phone (in a one way, her way conversation) of her suicide threats, or on the phone w/my brother whos trying to handle a mom that going off the deep end & verbally attacking his wife who runs crying to their room. They want out but can't leave mama alone. I tried to get her help to the point I went to court house, filled out papers & had an officer (I cant physically make her go) take her to hospital to force some therapy. Since she could say her name, date & who president was they wouldn't help. People say she needs therapy. We agree but we by law can't make her do nothing. Neither of us could handle it if she killed herself because we walked away & left her w/her spoiled, kick a fit self. Mama is used to having it her way on all things. She is no longer an addict but does take her regular meds. Some of her actions are dementia, some are pure meanness. Shes became an exact duplicate of her mom which was mean as a snake. The mentality of "I'm going to wallow in misery & make sure I keep you w/me". I don't mean to sound like a mean person but I know my mother & her mother & I know meanness from dementia. She's full of self pity & says nobody cares for her but were trying to do our best to help but she would rather wallow in the pity. She only hears what she wants to & only has feelings for herself. My brother needing support is driving me crazy keeping me tied up in mama's stuff. I'm doing all I can. She won't take no advice, suggestions or help & says I threw her on the street. I didn't. She had somewhere to go. She don't want "help" but somebody to tolerate her on going madness and misery. Legally I have no recourse in making anything happen. I wish I did. It's like she's dug a hole & standing in it. I'm putting a ladder down to her but she's throwing stones BUT if we don't stand there while she does, she's goina kill herself cause SHE wants peace!! I'm at a no win situation & I don't know what to do! I myself deal w/illness but she's not concerned about me at all. So, guilting her into help don't work. She won't let me finish a sentence much less try to guilt her into help. I have answers to help her but she don't want them. She is managing to keep two houses completely stressed out. I can't make her go see anybody & I'm not rich to be able to bring somebody in. She don't have much money but owns several pieces of property so she doesn't qualify for anything. She's very money hungry & always thinks we want something from her. I don't. I've never asked for a thing. She even asked my brother what would become of our home if we died!! She is either depressed, anger to the point she could hurt you, or being nice. One can switch to the other in a matter of minutes!! I'm exhausted and nerve shot. I don't know what to do. Her keeping me upset all the time causes the trickle down effect to my husband, who is a good man. We are financially strapped due to my illness so me getting therapy is not an option. I'm wearing down between trying to support my brother, running back & forth to mama (which w/gas prices is eating me up), listening to it ALL the time from brother & mother, trying to take care of my house, my illness, being a ear for my kids, being a grandma and just life! Getting out the bed is a struggle at this point. The stress is keeping me in a high level of pain since my nervous system malfunctions all the time due to Transverse Myelitis. I know yaw don't have answers but thank you so much for just letting me vent. I could write a book to fill in all I've skipped but space is limited & I don't expect yaw to read a book of my troubles. Thank you for your ear as my house is tired of hearing it.