kml - he has been suffering from covert depression (imho) for years. And yes he had a LOT of chemo before they even operated.
The man is depressed, and reuses to admit it. He says 'I was depressed but now I am fine'.
He could have a chemo brain - but I know other people who have had chemo and they are not like my xh. He flipped out in late 2005 and never really looked back.