The problem is that Barb has manipulated the situation so that Chris has to rely on Barb (and I mean from all the way back when Borb refused to get him help for his 'tism and basically trained him to be an unpleasant slob that can't connect to anybody other than Borb and can't take care of himself without Borb), and Chris knows that he relies on Barb, so he can't put any blame on her, even though she is the only one he can legitimately put any blame on other than himself. His need to blame shit on trolls is probably just some fucked up/idiotic defense mechanism so that he doesn't have to acknowledge that the one person he needs/loves is the one external person fucking his life up, and also so he doesn't have to acknowledge his own (limited) power to change the situation, because if he acknowledged that he had some power, he'd then have to acknowledge that he is the one that has to put the effort in to fix it.