wear sackcloth and ashes

To act in a way that shows one's penitence or remorse for one's misdeeds or poor behavior. Darren has been wearing sackcloth and ashes ever since his girlfriend broke up with him for cheating on her. There's no way to turn back time on the way I treated my brother growing up. All I can do now is wear sackcloth and ashes.

Common Names:

Name	Pronounced	Usage
Ajay	-	Indian, Hindi, Marathi, Gujarati, Bengali, Telugu, Kannada, Malayalam, Tamil
Dunlap	['dunlæp]
Age (1)	-	Frisian
Frederica	frə-də-REE-kə (Portuguese), fred-REE-ka (English), fred-ə-REE-kə (English)	Portuguese, English
Gedeon	-	Biblical Latin, Biblical Greek
Friedrich	FREED-rikh	German