忘得一干二净记得清清楚楚
[wàng dé yī gān èr jìng jì dé qīng qīng chŭ chŭ]
Literally, 'Forgetting something completely while remembering it clearly,' this implies that even when trying to forget, memories remain sharp and unforgettable. It suggests unresolved feelings or experiences that are hard to let go.