哑子吃黄连，有苦说不出/ 啞子吃黃連，有苦說不出yǎzǐchīhuángliányǒukǔshuōbùchūto suffer in silence
to be forced to suffer in silence or swallow one's grievances without being able to complain; literally a mute eating bitter herbs and having no way to describe the bitterness