Answer: whatsdoneisdone

AnswerCrossword Clue
WHATSDONEISDONE

"Don't cry over spilt milk"

WHATSDONEISDONE

Words of finality

WHATSDONEISDONE

"Forget about it!"

WHATSDONEISDONE
Doubt-dispelling words from Lady Macbeth
WHATSDONEISDONE
Tautological statement of finality
WHATSDONEISDONE"Can't worry about it now"
WHATSDONEISDONELady Macbeth's declaration upon checking the steaks at the cookout?