Who said "Death is the only certainty we have."?

This quote is attributed to Melisandre.

Death is the only certainty we have. - Melisandre

"Death is the only certainty we have."

Melisandre Death

"The night is dark and full of terrors."

"There is no night and day in the void, no time, only darkness and cold."

"I have seen the future in the flames."

"The Lord of Light demands blood."

"Death doesn't scare me anymore."

"Death and I are old friends."

"Welcome to my world."

"Death is just the beginning."