Who said "I won't forget you."?

This quote is attributed to Bucky Barnes (Civil War).

I won't forget you. - Bucky Barnes (Civil War)

"I won't forget you."

Bucky Barnes (Civil War)

"I'm with you till the end of the line."

"That's all that's left, isn't it?"

"You know me."

"I don't know if I'm worth all this."