What does a dream mean in which you read your own diary or write in it?
A dream about a diary suggests that you are trying to change or rewrite the past to suit your own needs. Think about what the diary says and how it is similar or dissimilar to actual events in your waking life. Or this dream symbolizes an important memory or event.
What does a dream mean in which you read someone's diary?
A dream in which you read someone's diary means you are curious about what drives someone or you want to keep someone's secrets.
What does a dream mean in which someone reads your diary?
A dream in which someone else reads your diary indicates that there is a secret that you are keeping. You have trouble telling others how you really feel.