Hi. Ok, so from what I have learned about it and seen from her book is that she wishes to be more mature but when she actually is and is expected to act that way, she repeatedly writes about it and complains. Basically, this would mean that instead of following her parents wish to be mature or to act like a lady(teenager) she does the opposite and realizes what this comes with. Then she doesn't like it as much as she did before she is a teenager despite saying how much she wanted to be. As for evidence, I don't know off of my head, but know her diaries mention it several times. For the explanation, Anne explains her desire to be so much but then starts misbehaving a bit and that comes with facing her family and friends opinions which she doesn't like. Hope this helps you out as a basic explanation.
