@Rogojinen
The core issue is she wants a break from life, her curse, her disciples, and be herself.
Its why she set up the spell and array to kill herself.
She not revealing herself to her disciples is because she believes they themselves need to grow up and support each other to stand up on their own without her.
Its why she run away from them.
However, you're right, after seeing 2 of them become deranged, you would think she would reveal herself to them to stop their behavior.
I don't think she could easily prove herself to be their master to specific ones. Although, 4 people already know her true identity. The sleep deprived one even being in direct contact with her couldnt even figure out it was her.