Possible Clues:

• 'There can be no changing things now,' redundantly
• 'There's no going back'
• "You can't change the past"
• "Take my advice: no use crying over spilled milk ... "
• 'Take my advice: no use crying over spilled milk ... '
• Lady Macbeth's declaration upon checking the steaks at the cookout?
• "Can't worry about it now"
• Doubt-dispelling words from Lady Macbeth
• Tautological statement of finality
• ''Forget about it!''