It is reasonable to admit that the characters of Nora and Torvald are the only two who lack the common sense to discern appearance from reality in the play A Doll's House. Yet, as the play progresses, it is arguable that, out of the two, Torvald is still less aware of his reality than Nora.
Nora's tendency to act in a playful, childish and immature way is a result of her upbringing. While the story does not ascertain how Nora was raised, Nora's own words concede that life with her father was no different than her life with her husband.
Here I have been your doll-wife, just as at home I used to be papa's doll-child. And the children, in their turn, have been my dolls. I thought it fun when you played with me, just as the children did when I played with them. That has been our marriage, Torvald.
Nora cannot be blamed entirely for having played the character of a "doll". She even claims that she has dwindled from happiness to sadness, from time to time, while playing her part. However, it is obvious that Nora has tried many times to make herself worthy and valuable. Hence, when she borrows money from Krogstad in order to fund a trip that would help her husband's life, she does this under the assumption that her good deeds will be rewarded with gratitude and respect. Little does Nora know that her husband, Torvald, is too preoccupied with the superficiality of life to look deeper into her sacrifice. He reproaches Nora for having acted in an "indiscreet" manner, and he sullies her hard work with his condescending anger.
It is during this last cruel reality check with Torvald that Nora realizes that Torvald will only be pleased with her as long as she is entertaining and enabling. Any detour from that pattern of behavior would just make her plain and annoying to him. Here is where the roles switch: while Nora "wakes up" from the fantasy that she lives in, Torvald refuses to let it go.
This is because, when Torvald realizes that Krogstad no longer poses a threat to potentially humilliate him or Nora, Torvald wants to quickly undo what he has done to Nora's ego. Yet, it is too late. Nora has had enough of playing the roll of a puppet and she tells Torvald that she will simply leave. She much rather sacrifice herself again, because this time it will be for her own sake. No more sacrificing for others. Nora has finally grown up.