In The Glass Managerie, Tom Wingfield is the older brother and provider for his mother, Amanda, and sister, Laura. Tom and Laura's father left the family a long time ago, and they have not seen him since. Tom, the older brother, feels the burden of having to take care of his mother and sister. He begins to resent the fact that he must provide financially and emotionally. It takes a toll on him. That is why he decides to leave home.
Laura wears a brace on one leg and is painfully shy. Her mother feels it her duty to find a suitor for Laura. She asks Tom to help. Tom brings Jim to the house for dinner, but did not realize Jim was engaged.
Laura, unaware that Jim is engaged, finally opens her heart to share with Jim that she had a crush on him in high school. The two of them share an intimate moment, only to be interrupted when Jim remembers he is engaged.
After the fiasco of learning that Jim is engaged, Tom's mother explodes in anger because Tom brought home an engaged man for Laura. Of course, Tom had no idea he was engaged, and his mother's arguing just helps him make up his mind to leave home.
In fact, instead of paying the electric bill, Tom spent the money on the merchant marines. By the end of the play, the lights go out. This is symbolic, meaning the end for Tom. He has made up his mind.
Laura and Amanda will have to figure out a way to make it without Tom. Ironically, Tom does exactly what his father did. He abandons his family, but considering the type of argumentative mother he has, who can blame him?