Story where character overhears lie, acts on the lie, to his detriment, liar feels great remorse

[Amy]

I'm looking for a story, preferably from a work of literature or a play, involving the following plotline: Character A tells B a lie. Unbeknownst to A and B, C overhears the lie (or C comes to learn of the lie subsequently). C believes the lie to be true. C acts on the lie, to his detriment. When A learns that A's lie was the cause of C's demise, A feels tremendous guilt. A takes herself to have wronged C in lying to B.