Cut to the quick

    大伤感情

    A: Why is John insisting a breakup from Mary?

    B: Her remarks about his inability to earn a decent living cut him to the quick.

    Note: "Quick" is slang for the flesh under our fingernails. The nail is hardened and rough, hence insensible. In contrast, the flesh underneath the nail is tender and sensitive. In "cutting to the quick," the quick refers to the living sensitive part. Metaphorically, the pain of being emotionally hurt is similar to being cut through one's nail. A similar expression is to "cut someone to the bone."