Laura is presented as an extremely shy and sensitive person. Her shyness is emphasized even more by being contrasted with Amanda's forceful and almost brutal nature. We are made aware almost immediately of Laura's overly sensitive nature. She is so nervous that she cannot even attend business school without becoming violently sick. She is frightened and nervous when Tom and Amanda quarrel. She possesses a glass menagerie which she cares for with great tenderness. And she has withdrawn from the world — a withdrawal from what is real into what is make-believe.
Laura has a slight physical defect — a limp — but she has magnified this limp until it has affected her entire personality. Laura's oversensitive nature makes her think that everyone notices her limp; it becomes for her a huge stumbling block to normal living. She cannot get over it and into the real world. Her inability to overcome this defect causes her to withdraw into her world of illusion. The limp then becomes symbolic of Laura's inner nature. As Tom says, it's not just Laura's being crippled that makes her different, but she is just different. So she lives in a world of old phonograph records and glass animals.
And then the gentleman caller arrives. For the first time we see Laura's inner charm. She is fresh and pretty, and she does have charm — not as Amanda wants it, but in her own individualistic way. She is even capable of forgetting her physical handicap. She responds to Jim because he responds to her difference. With Jim, she sees that her difference is an asset and not a handicap. But ironically, she leads Jim more into her world than she enters into his. Thus, when the evening is over, when the unicorn is broken and the hopes are shattered, Laura does not have to retreat back into her world because she has never left it sufficiently enough to necessitate the retreat. Quite the contrary, now that the unicorn is broken, is ordinary like Jim, she sends it forth with Jim, and she remains in her unique world with the other unique glass animals.