Related Clues:

• 'Alas!'
• 'Too bad!'
• Compassion
• Repent
• Sentence modifier, at times
• Sackcloth and ashes
• Compunction
• Wish undone
• See 8-Down
• Rue
• Lament
• Feeling for the unfortunate
• See 35-Across
• Feel bad about
• Regret