亲爱的那并不是爱情
[qīn ài de nèi bìng bù shì ài qíng]
Translating to 'Dear, That Wasn't Love,' it refers to a sentiment that despite all the experiences shared, at its heart, what existed was not actually 'love.' Often used to describe unfulfilled affection or mistaken emotions, suggesting deeper insight or maturity has been achieved.