[ar81]

The concept of adulthood is a legal concept.
But people have different stages in evolution.

Approximately from 15 to 24, people are trying to find their own identity, and it is hard for people to distinguish between "what I want" and "what you want" and it becomes hard to understand someone else because you do not even understand yourself.

She is too young, like a post-teenager. I have been with several groups of teens and young adults which engage in cultural activities. You notice that kind of identity problem. In those projects I have had to help them to solve some aspects of their lives too. When people grow up they pass through different stages.

Instead, Tonton Macoute, at your age you might now be in a different stage: "where do I fit in this world".

This transitional period is what I called "immaturity" as it will be hard for her to understand where you are, because she is in a different stage.

Being in a different stage should not be a problem if you understand the differences. And at some point she will be in the same stage you are. There is nothing wrong with it, it just requires to understand where you are and understand each other.