Can I put my mother in a facility without her permission, she's not of sound mind, refuses to go to a doctor to get proof of this.

My mother in her late 70's suffers from dementia, my siblings and I are all married over age 50. My brother and sister do not want to put her in a facility. She has insurance for this. My mother has become nasty, insulting, very combative over everything. She chased people out of her life. She refuses medical treatment. How can they make a diagnosis without her permission? She slapped me infront of my wife. She can't live alone, she eats rotted food and can't properly take care of herself, let alone the animals or her house! Everyone is in denial here. My siblings are ignorant people. They don't want to listen to other people with more knowledge.. A very dysfuntional family.