] Though her affections for Miss Thorpe are, in my view, misplaced and unwise (I recall detesting Isabella Thorpe my first trip through the book), it is very like a teenager to grasp onto the first youthful company given over to her when she has spent the whole of her visit to that point in the company of a very silly and very matronly chaperone.

I am firm supporter of the "nurture" side of the nature vs. nurture argument, and Catherine supports this. She has not had the direct attention of her mother to guide her into womanhood, Mrs. Allen is hardly someone to pattern her behavior after, and Isabella, being closer to her age and so self-confident, besides showing interest in her friendship (feined, in my opinion, but Catherine doesn't realize that) would certainly seem like someone to look up to and mimic.

I get the impression that if she had more suitable role models (where is Elizabeth Bennet when you need her?) she would grow into a very accomplished and mature young lady.