When a person repeatedly brings up the same thing, it's often not because they can't let go, but because that experience has left an unresolved pain in their heart. They need to keep talking about it to understand and process it. Psychological and emotional trauma can indeed persist for a long time and be triggered at certain moments, causing a person's mood to quickly become low. Even if there is happiness and brightness in life, these memories can still bring temporary shadows. But this doesn't mean the pain can't be alleviated; with time, understanding, and support, those shadows can gradually fade, and the light will slowly shine through again.