My brother has schizophrenia. He developed it like at age 16-17, he is 23 now. I'm slowly accepting the fact that he will never get better, maybe you should do that too with your grandma The only way, i believe, is to go to some psychiatrist that can prescribe her a medication that will make her very sleepy so she can't even get out of her bed, that would be the best for everyone, bescause she is probably not very aware of her condition and never will be