Don't say you don't care, that's just a cover-up. The real indifference is to say nothing, just let everything pass; to open your eyes, watch it slowly pass by, and you will remain indifferent; even if it stimulates you, you will not be moved. Even if it is painful, sad, or nostalgic, you will never think of it again. Therefore, whether you care or not has nothing to do with whether you say it out loud, it is in your heart, on your face, and in time.