Nora keeps up a facade every day that she lives. She pretends to be happy when in fact she is not. She wears a mask just as she would wear to the masquerade ball.
Nora lives in a man's world. She has no rights. She has no identity. She is Torvald's wife and her children's mother. Nora does not really know who she is. She sings like lark, all in an appearance to be happy. She plays games and does whatever she can to please her husband, Torvald. She risks her own reputation by borrowing money to save Torvald's life.
Everything Nora does is based on pretense. She borrows the money behind Torvald's back. She does not desire to upset him but she knows she must save his life.
Nora carries around the heavy burden along with the stresses involved in being in debt. She manages to pay on the debt but she must keep secrets from Torvald for she wishes not to anger him or worry him.
Nora is living in a pretend world. She does not have any authority. In the nineteenth century, women were seen as pretty objects or possessions with no merit or value. Nora is intellectually handicapped due to living in a man's world. Her husband does not see the business sense she really has. He does not respect her intellect. He does not appreciate how valuable she really is.
Truly, Nora keeps up appearances. She pretends to be happy. She wears a mask to hide her feelings and emotions. Nora feels she must be the perfect wife:
Nora is the "doll" wife of Torvald. She is sensitive, sensible, and completely unaware of her own worth until the last act of the play. She initially appears flighty and excitable. Nora is most concerned with charming her husband and being the perfect wife.
By the end of the story, Nora's eyes are opened. She takes off her mask. Ultimately, she leaves Torvald and sets out on a journey to find her true self.