What Do Mood Swings, Constant Naps And Hallucinations Suggest?

My husband is concerning me with his mood swings and constantly napping and the most concerning to me is that I catch him having slient convrrsations to himself in his head. He will have head movement and also shrug shoulders and put hand up. He thinks I should just leave him alone that he has always been like this. How can I get him to see this is not normal and what could be going on.