What can be done about an guardian who abuses their power?

My mom and I are very close and has always been since I was little. I have never gone without a day of not seeing her or talking to her on the phone. We have a very special bond. My mom started to have dementia. She gave me POA. She disowned her other children years ago because of what they had done to her. She was never close to her other children. My parents were married for 45 years until my dad had an accident and started to have mental problems himself. My father is not my mom's kids father only mine. My father always hated my moms kids. But my father and I were always close also. Once my moms kids saw my father having mental problems they brainwashed him to hate my mom and his only child and his only grandchildren. My mom's kids not only made my parents loose their home but convinced my father to divorce my mom and then they stole from my mom and I and took my mom's baby grand piano. My mom moved in with me and then they helped my father take my home away from me. We all had to move in with friends. My mom made me promise her not to ever let her kids hurt her again and she never wanted to see them again. Years had passed and I did my best to keep her kids away from us. Before my father died my mom's kids had my father change his will and he took me and his grandchildren out of his will and left everything to my moms kids. Then they finally found us and kidnapped my mom one night from were we were living. My mom was diagnose with dementia a few months before. They tried to get my mom to write a letter to the court saying she is afraid of me but I think the judge saw through that one. I went to court and the court allowed my mom to stay with them temporary and then the court appointed a guardinship for my mom. They put my mom in a home. My mom and I shared storage units with all of our belongings. The court ordered everything to be sold and used for my mom's expenses except the court allow me to go into the units and get my belongings. The guardian for my mom would not allow me in and always gave me excuses why I cant go in. But she allowed my mom's kids, my ex husband and his family to go inside and take what ever they wanted. The court order stated only the guardian, my sister and myself are the only ones to go inside. The guardian allow my brother to rent another unit and stored my belongings along with my moms in it. The guardian said she didnt have to make a list of what she sold and time I go to court everything will be gone. And what a surprise the guardian put my mom in a home across the street from my mom's kids home and made it along ways from me. What can be done with this guardian I believed she has also stole from myself and my mom along my moms kids. The guardian sold my moms classic car with I was trying to buy but she threatened me with that so she sold it to her friend real cheap and then he sold it for thousands of dollars more. She also had her brother going though our belongings and take things. People at the storage saw not only her brother but the family loading things into their cars. This is abuse of her power and I want to know what can be done. She should have to make out of list of what she sold, how much and what she did with the money. I had my receipts to prove some of the expensive things were mine. She didnt care. When my mom's kids took her that night they also made her change the POA. Thats how I lost the POA. Her kids are so wicked not only did they take everything from my father they took everything from my mom. They cremated my father and spread his ashes so they would not have to use to much of his money more for them. My father didnt believe in cremation and he wanted to be buried. My dad was a veteran so his funeral was paid for but they wouldnt know that cuz they didnt really know him or cared. My sister pulled the plug on him at the hospital and listed herself as his daughter on the death certificate.This is just a small part of the story there is more. I want this guardian to be a counted for what she has done so she doesnt do it to anyone else. Any ideas would be much appreciated.