Minnow
Surely his Doc`s are taking notice of his weight loss? He will find it very hard to get better with the small amount of calories and nourishment he is able to take in. He is obviously one stubborn Englishman..I know what you are dealing with, I am married to one , an Englishman that is! Have you seen The Drink recipe ? lots of calories and easy to get down, even though it might take him all day.
1 tblspoon Carnation
1 tblspn Ovaltine
1 pkg Carnation instant breakfast
1/2cup whole milk
1/2cup half and half
2 cups ice cream.

He must get more food in his system than he is presently taking.. if he does not have one , get him a liquidizer if he cannot tolerate anything more solid than custard.
Just show up with it .. hopefully he wont be rude enough not to let you in.
Depression is not unusual at any time throughout the treatment process, a lot of times they feel worse after treatment is over, physically and mentally.
Hang in there with him Minnow , he needs you even though he won`t admit it.
Marica