It seems this friend is taking up just about all of your time, and it is you who is doing all the cooking !!.
I'd certainly drop the two courses all of the time. And of course there are all the little snacks/treats. I'd think £40 per week was getting off very lightly. Also have a few meals of scrambled eggs/toast, beans/toast, egg/chips. tin of soup and a sandwich.
What about if he was to provide a few meals throughout the week, at his home. That's if you want to still spend as much time with him.
However, you do say that you like your own space and (if it was me) I'd be inclined to be honest. Arrange to have a day/afternoon to yourself as and when you wish. Go see another friend, or make new friends. At the moment it sounds like he has you in a corner that contains just you and him..... and still he pressures to see you more.
I agree with previous posters, is this a platonic friendship, or is he looking for more.
And please forgive me if I overstep the mark here, but I hope he wouldn't be looking for a housekeeper/cook on the cheap.