笑靥如花你管我是真是假
[xiào yè rú huā nĭ guăn wŏ shì zhēn shì jiă]
It roughly means 'you worry about whether my smiling face is true or false', implying the person doesn't care if the other person sees their smile as genuine or fake. It could mean that the person has seen too much and experienced too much, thus they have become indifferent, uninterested in what others think, feeling free inside.