I ought to find a well-known book and sit down to work it out.
But I'll give you one of mine for now.
In one of the King Arthur stories, Queen Guinevere is having adulterous sex with Lancelot, who's climbed in to her room through her bedroom window. Because the window bars are rough, he cuts his hand, and leaves blood on her bedsheets, but neither he nor she notices because they're busy shagging and it's dark.
In the morning, someone sees the bloody sheets and immediately decides it's sex-related blood, and that Guinevere must have been sleeping with another knight who was staying in the same castle (not Lancelot). They accuse Guinevere, and she tells them that it's not true, and that the blood is there because she had a nosebleed in the night.
Only thing is, the narrator tells us that she honestly does believe that's the truth of it.
So, we have to believe simultaneously that she's guilty of adultery (because she is) and that she's being truthful (because she is). These two things can both be true at the same time, but IMO they are perfectly ok as cognitive dissonance, because their implications about her character are contradictory.
There is a huge amount of epistemic disruption here, because we can't figure out whether Guinevere would have lied if she'd known, and the narrative is full of 'what-if' bits: there's too much information, and too little, to make a neat plot.
But, the crunch is that, if you think about it, Guinevere has just demonstrated that she doesn't even know her own body. She can tell a lie about having a nose bleed, because she doesn't even know her own body didn't bleed. The men around her know better than she does what her body has been doing, because they correctly guess that she's been committing adultery and don't believe it was just a nosebleed.
I find that really fascinating (if totally odd!) - because, why does the author write it like this?! What's to be gained in having Guinevere sincerely believe in something as trivial as a nosebleed? IMO, what's gained is that it forces us as readers to start seeing her as inherently unreliable even when she thinks she's truthful.
(This story gets dark, btw - Guinevere's eventual fate in most Arthur stories is incest and/or rape, and being sent/fleeing to a nunnery to die.)