Isn’t Rey’s foolish hope just the lie she tells herself? Like people can be logical but also be illogical when it comes to family or daddy/mommy issues.

It’s possible that the hope of her parents returning was what allowed her to survive for so long. It was her willpower to preservere because of that hope. So she she stayed on Jakku because she thought it was only a matter of time for her parents to come back for her. It could be any day now, so she was waiting for them, because that was what she wanted more than leaving Jakku or being a hero, she wanted to be with her family again.