Who said "I can't do this alone."?

This quote is attributed to Arrow.

I can't do this alone. - Arrow

"I can't do this alone."

Arrow Friendship

"My name is Oliver Queen. After five years in hell, I have come home with only one goal: to save my city."

"I'm not the man I was."

"You have failed this city."

"I'm a monster."

"Friendship is built on trust and honesty."

"True friendship is worth more than gold."

"Good friends are like stars, always there even when you can't see them."

"Friendship means sacrifice."