Possibly the most realistic, calm and introspective Studio Ghibli movie out there, Only Yesterday tells the story of a twenty-something and her childhood. It's not exactly action-packed, but it's still fascinating to see this life unfold.
Taeko realizes she has been clinging to her childhood. As she's on vacation she finds herself flooded with memories of the optimistic innocence she used to have, as well as some more negative things that left their marks on her too.
Anyway, it's a lovely slice of life-ish coming of age story that shows you don't have to carry everything from your childhood into your adult life, that it's okay to let go of certain things and move on. And it shows it in a beautiful way!