Depression in a dream is read as heaviness given a shape — grey light, slow movement, weight on the chest. Tradition takes it as an inner state asking to be noticed, not a verdict. Watching someone else in that state points to worry for them, or to seeing your own mood in another face. Light breaking through, or colour returning, is read as hope and a turn in feeling. If that heaviness stays with you in waking life too, sharing it with someone you trust can lighten it.
Does the traditional reading fit your dream, or did it mean something else to you?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.