Who said "To give up is to deny the very essence of who I am."?

This quote is attributed to Lady Sif.

To give up is to deny the very essence of who I am. - Lady Sif

"To give up is to deny the very essence of who I am."

Lady Sif Perseverance

"I am a warrior of Asgard, and I will not falter in the face of darkness."

"Strength is not measured by the power of one's blade, but by the resolve of one's heart."

"A true friend stands beside you, not behind you."

"We are forged in battle, but refined through compassion."

"Perseverance is the key to success."

"Don't give up on what you believe in."

"I've been through worse."

"You learn to live with the pain."