Yes, I know that is your opinion. You are not harmed when you choose to kill yourself. The role of the state is to protect you from harm - including self-inflicted harm. Valid, or coherent? Because you will dismiss any morally-based example as invalid, I'm sure. The religious argument is typically that people have no rights over their own bodies, as they did not create them. All choices regarding life and death must be made in favor of life.