Responses
or just really bad social anxiety
Add in abuse from peers, adults (I think her tutors and possibly even her parents really screwed her over. There is no way that would continue if they cared) in her life.
If you think about it, her having a mental illness really sheds light on why she never grew out of some at least some habits.
I know this is probably super late but I think the previous chole had whats know as anthropophobia (fear of people) because the symptoms that she was depicted with are very similar.