Guichet: seniors' right to self-determination

When a doctor decrees that a person no longer has the capacity for discernment, they lose their right to self-determination, such as deciding what to do with their money, or saying what they want in terms of medical treatment. She also no longer has access to assisted suicide. How is this capacity calculated? What rights do relatives have? What steps can be taken to prevent the appointment of a curator from outside the family? What is a placement for the purpose of assistance?