分手的时候才知道伤心
[fēn shŏu de shí hòu cái zhī dào shāng xīn]
'Only When We Parted Did I Know Grief.' Often refers to someone realizing true sorrow after experiencing separation or breakup, it shows realization comes late sometimes. Real feelings surface especially during moments of saying farewell, when people may understand just how important a person really was, or just the difficulty accepting changes leading up to sadness.