I like her
There was no need for Bai Li to seek help from Shen Yu, because technically she could have achieved what she wanted and she was confident in that. But why would she just delay reaching to her goal?
Bai Li had actually admired Ning Xi for years because of how similar they were. They both focused on body Cultivation more and given how much Ning Xi had achieved, it was no wonder she was Bai Li's idol.
But that wasn't it. Bai Li had seen and observed Ning Xi for a long time so she knew what type of person she was. After all, Ning Xi was very easy to read.
Not only that but the short time she spent with Ying Yue had already told her the kind of Sect they were in. They were good people who loved each other and she could see that clearly.
As she had never really experienced the feeling of being loved properly, she wanted to know to know and feel that. That was one of the reasons she had decided to enter the sect.