It's an interesting issue, which brings up the vexed question of compulsive liars, some of whom don't believe they are lying. I think various branches of psychology have struggled with this, and have produced various ugly terms such as 'disavowal' and 'scotomization' (blind spot), to describe it. They basically mean blanking out a part of reality. For example, you can get someone who regularly steals stuff and doesn't think that they do. Of course, some of them probably do know this, and deny this, but I think there are people who genuinely don't think that they did what they did.
I suspect that we have no words to describe someone who systematically misrepresents, moves goalposts, self-contradicts, and so on, and doesn't appear to see anything wrong.