He's actually going to go through it. If I was him, I'd be doubting any signs of secret messages. This could be just our protagonist's paranoia for all we know.
to be fair. She never lied. She said she would come back, she didn't say she was abused, she said she wanted to leave and that they weren't here real family. That's it.
So far they haven't laid a finger on him but he is the one thinking of murdering them and has tried to do so twice, one with a rock and another with a gun.