I was so confused when she started talking about it! It made no sense with the scene. It was only when the narration explained her beliefs that I understood what was happening.
Maybe the mother is written to have a warped idea of mindfulness? I'm pretty sure mindfulness is supposed to be more acknowledging how you feel and the reasons for why you're feeling that way. Like, the opposite of ignoring your feelings.
The book's already showed a couple signs prior to this of him hiding negative emotions from his mom, and I don't blame him after this. I wouldn't feel safe expressing myself around her either.
That's not what practising mindfulness means!
What a horrible behavior, particularly coming from a mother.