Who said "I've learned that love and vigilantism don't mix well."?

This quote is attributed to Arrow.

I've learned that love and vigilantism don't mix well. - Arrow

"I've learned that love and vigilantism don't mix well."

Arrow Love

"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."

"I love my wife, but sometimes she drives me crazy."

"Love conquers all obstacles."

"Love is patient, love is kind."

"I'm not stupid, I'm just in love!"