What next?

The plan was to have my brother and his wife and son move into my mom's home to care for her. My mom thought that it was a good idea to keep her in her home as long as possible. From the moment they moved in, she did nothing but accuse everyone of stealing from her. She's so angry with us, we know it is the disease, however it is getting harder and harder to assist her. She throws tantrums, pulling her hair and crying "I just want to be like I use to be" once she calms downs she tells us how she is happy we are helping her. My brother's wife has since moved out because my mom was really mean to her. My brother is still there at night, however the situation is not fair to him and his family. My brother and I have to work getting outside help is not going to go over well with mom because, she doesn't trust anyone coming into her house...she is becoming a danger to herself. We don't know what our next step is....