苦不堪言言不由衷
[kŭ bù kān yán yán bù yóu zhōng]
Expresses an extreme state of suffering and being overwhelmed, where even speech fails to properly express one's inner feelings. '苦不堪言' indicates great distress and unbearable hardship, making it difficult to describe or verbalize. '言不由衷' adds another layer by suggesting words come from a place other than one’s true feelings, implying dishonesty due to this immense pain or societal pressure.