Who said "You can't kill what's already dead inside."?

This quote is attributed to Nebula.

You can't kill what's already dead inside. - Nebula

"You can't kill what's already dead inside."

Nebula Death

"I didn't ask for this life."

"You're welcome."

"I will kill you slowly."

"Gamora may have stolen your money, but I will steal your life."

"Death doesn't scare me anymore."

"Death and I are old friends."

"Welcome to my world."

"Death is just the beginning."