Dad visited today, he seems to get an obsession about something these days and whatever I say or do it makes no difference. He seems to have a great stubborness about him that I do not remember, he gets very determined and he will do something regardless! I feel very depressed about it as there really does not seem to be any reasoning with him and he almost gets very angry and argumentative about it especially when he wants to buy something that does not exist but will spend weeks looking for it then actually does not buy it or find it, what a life! Family members say to me - oh leave him to it!, he wont find it anyway! But it feels such a waste of his life, so unlike him. Is this part of the disease?