无力挽回就要懂得放手
[wú lì wăn huí jiù yào dŏng dé fàng shŏu]
It means 'If something cannot be saved, you should learn to let go.' This Chinese username often implies the feeling of helplessness and resignation after realizing some situation, typically a relationship that's irredeemable. It suggests a mature understanding that it is wiser to move on when something significant can't be mended.