你笑我有病我笑你神经
[nĭ xiào wŏ yŏu bìng wŏ xiào nĭ shén jīng]
The phrase 'You laugh at my madness, I laugh at your nerves' expresses a mutual mockery between two parties. The holder could be conveying that while people mock them, they equally find humor or amusement in those mocking them—possibly implying an attitude where no one is above reproach, highlighting a reciprocal defiance.