Who said "Regret is a poison that lingers far longer than death."?

This quote is attributed to Severus Snape.

Regret is a poison that lingers far longer than death. - Severus Snape

"Regret is a poison that lingers far longer than death."

Severus Snape Life

"It is our choices that show what we truly are, far more than our abilities."

"Dunderheads. All of you. Particularly you, Potter."

"I can teach you how to bottle fame, brew glory, even put a stopper in death."

"One sip of this potion would make a man invincible."

"Life is meant to be lived with passion."

"Life is what happens when you're busy making other plans."

"Life is a journey, not a destination."

"Life's too short for regrets."