I would add that both Tom and Nora are victims of their immediate social and economical status. If either of them had been rich, or born with a silver spoon, chances are that the worries and the risks that they took would have never been a part of their realities.
They are also loners: They seriously need some "alone time" to reinstate their roles within the family unit, within society, and within their own fate. It would be easy to dismiss Tom and Nora as completely distinct personalities, but (in reality) they are the product of their parents: Of needy, misunderstanding parents who continuously maintained their old standards and insisted on conveying them onto their children. That is the major reason why they are so similar.
This unlikely pair actually do share several similarities in their domestic situations and in the choices they make. Both Tom and Nora are developed as intelligent, sensitive individuals who are trapped in unbearable circumstances. Tom's dreams and desires are thwarted as he works in an intolerable dead-end warehouse job to support his impoverished and helpless mother and sister. Because of the financial desperation of the Great Depression and Tom's sense of responsibility for his family, he is not free to claim his own life.
Like Tom, Nora is also trapped by circumstances. She has no power or equality in her marriage or in her society. She is also ensnared by a financial obligation, the secret bank loan she had obtained in desperation by forging her father's signature. Nora cannot claim her life or live authentically so long as she remains in her marriage.
Ultimately, both Tom and Nora leave their families. Tom abandons Amanda and Laura to travel the world and pursue his dreams. Nora leaves her husband and, most painfully, her children in order to live as the woman she really is--strong and capable.
Tom and Nora both pay an enormous price for their freedom. In "The Glass Menagerie," we know that although Tom leaves, he is never really free; he is haunted by the memory of his sister. As for Nora, her story ends as she walks away from her stifling marriage. We can only surmise what her life will become.