A lot of this feels a little "glutton for punishment". Like, they keep f*cking with him yet he continues to interact..
But when you're in the thick of it, involved with a project you really want to succeed, and which has an impact on your reputation, it is so, so easy to convince yourself that it's all a misunderstanding and you just need to keep trying. Particularly if you are a good-hearted person yourself. I've certainly suffered from this (and very few people who know me would agree that i need to be more of an arsehole!).