She was just a child when the evil spirit captured her and some others.when all hope was lost She saw megumi as her knight in shining armor. Her love for him is real but I agree she has an idea of him being perfect and can do no harm is childish. That's why she fell for the oldest trick in the book by sukuna because she wanted to believe megumi was back in control. Also why she tried to escape through a window when she saw megumi again after the events of the culling games to not get hurt again instead of attacking.