巧克力太苦苦到心酸
[qiăo kè lì tài kŭ kŭ dào xīn suān]
'The chocolate is too bitter it tastes sour and heart-wrenching'. Usually chocolate is sweet. This saying reflects a sad and disappointed mentality through this contrary metaphor. Maybe some things you once enjoyed have now turned unpleasant. The bitterness of the process made the person nostalgic and melancholy for the past.