I would disagree with that. She has her moments where she actually does seem quite old, and even wise, but she never really grew up and became an adult - she's very immature and selfish, and though it could be argued that it's because she's so old and tired of life I think at least part of it is due to her being stuck in a teenager's body, with a teenager's hormones and lack of foresight and stuff.
(no subject)