I have an appointment this afternoon to put my cat to sleep. He is 18 1/2 years old. He can hardly see and limps when he walks as his joints are aching. He pees when he sleeps. He eats fine but all he does is lay around and does nothing else. Am I doing the right thing? He is quite old but I just fear I'm doing the wrong thing. Am I? Or is this the best thing for him? Best thing to ease his suffering. His quality of life is poor.