I believe the woman was giving a genuine but unsettling smile, similar to the one Tash had shared before she departed. This kind of smile suggests a mix of emotions but ultimately indicates a sense of liberation or resignation.
I think she was smiling the same kind of real smile that Tash had smiled just before she left. It's a scary smile. It's a smile that means there is nothing left to lose. That you are free
. The scene captures a moment of complex emotions, blending relief, fear, and a sense of finality, hinting at profound changes or an acceptance of a difficult truth.