What made Anne think of adults as stupid?

Anne continues to get frustrated with the adults in the annex. They argue and complain constantly. They are also quick to offer advice to her about her personal life which she finds annoying. She feels as though Peter is the one bright light in her life, and they spend a great deal of time together. The adults notice how much time the two of them are spending together, of course. Mrs. Van Daan teases Anne, asking if it's all right to trust the two of them alone together.