Thinking about this, it would be kind of interesting if Naoi calls her out for the idealized version and pushing her expectations on Kurumi and this actually gets her to reflect and figure out how to support Kurumi. Naturally only after a sufficient number of chapters of drama and Kokoro making the situation worse, but you have to admit Naoi is the most suspicious based on what she knows.
Naoi narratively fills the role of being outside society and therefore able to see the true relationships for what they are, so it seems like "does this person actually care about Kurumi" would be something she is trying to figure out. Kokoro is herself also an outsider with bad experiences socially, even if not as severe as Naoi or Kurumi from what we've seen, so recruiting her rather than defeating her might be an option. This might also moderate Naoi just a little bit, as she would want to support someone supporting Kurumi and therefore have more of a social circle than Kurumi only.
This doesn't seem the most likely based on what we've seen, but that's exactly what would make this an interesting way of approaching the story without everyone being irredeemable, compared to just doing the predictable thing. I am fine with it if Kokoro does undergo the slide into insanity that people are predicting, however, as this would be more dramatic in a story that has thus far had the drama dialed up to 11.