Simon, this guy probably has about 10% of his motivation for doing this actually because of you, and the other 90% is because he's bored, or mad, or unhappy, and so on and so fourth.

reasoning with people like this never works. Their brains never truly grew out of the stage of throwing a tantrum in the grocery store when mommy got you Life cereal instead of Fruit Loops with a toy in the box.

Really, I feel sorry for this dude.