Unfortunately, Laura, like her mother, cannot always stay in this fantasy world. She has a more difficult time staying in an unrealistic world freeing herself from the pain of her present one. The broken unicorn represents her fractured life; she is not physically whole with her limp and emotional fragility. She clearly recognizes the truth about herself, as she says to her mother: "I'm crippled!" (Williams xx) That is, she cannot complete Amanda's expectation; she cannot be "as popular" as her mother. Every once and a while, she forgets who she is. She forgets that she cannot live up to her mother's or even her own personal expectations. For example, she has fragile hopes that she will shine liker her glass and be something special when Jim comes for dinner. She is instead resigned to her continually despondent and lonely future. It is Jim, the representative of reality, who makes both Laura and Amanda see the world for what it is.
When the play comes to an end, the Wingfields are more in touch with reality as they were previously. Amanda says she has put aside her "silliness" and realizes more fully that she cannot change Laura. She blames Tom for his selfish dreaming, but actually it has been her selfish dreaming all along that caused such problems. People cannot be changed from who they are, even loved ones.
Williams, Tennessee. "Glass Menagerie" Literature, an Introduction to Reading and Writing. Eds. Edgar Roberts and Henry Jacobs. Upper Saddle River, New Jersey: Pearson Education, Inc., 2007, xx-xx