Sima You Yue still tightly clung to Emperor Qing Dao in her heart. It could be because he was the first emperor that she had interacted with. Or perhaps, perhaps because he told her that he hoped that she would be able to change the heavenly law.
She was not very powerful yet and was still unable to feel the effects of the heavenly law. The effects that she had come in contact with were just her experiences with the lightning calamity as well as the lightning punishment that would come as a result of defying the natural order that the Feng Clan had talked about.
If he wanted her to change the heavenly law, she felt like this was something akin to a dream.
However, when she thought about how Aunt Feng was an emperor that was not acknowledged by the heavenly law and how countless cultivators were locked at ranks under emperors because of the heavenly law, she felt like the heavenly law was a little unfair.