My mother has touch mania.she thinks everything outside our house is dirty.so she keeps cleaning everything whatever enters our house.If a guest comes she feels disturbed thinking that the guest brings dirt into our house.as soon as the guest leaves she starts cleaning our house even at night.She always remains stressful .Our life is disturbed too.we cannot invite any friends.We are living like prisoners. She is aware of her problem.But cannot do anything. How can this be cured?please help..