She seemed to have some sort of plan with the young master, her father seemed to be quite the scholar and she seems to live in a hut in the forest. The appareance of the mc in chap 1 threw this plan to the gutter.
Reread chap 1-2 and pay attention to her expressions and the dialogue.
Remember she's a weak woman in a society where she won't count for shit compared to a man.
So, when she has to choose between:
A - Go with the dude who just told you he's not a cultivator, just a regular chump, and oppose the young master, angering him in the process and risk to be passed around to his clique like a toy
or
B- Dispose yourself of the dude and get back in the good grace of the young master.
What would you choose if you're a calculative lady?