Is Amanda is really unstable or is she just eccentric?
In other words, many readers believe that she’s got expectations for her family that verge on absurd fantasies that have no chance of coming true.
Like the others in her family, Amanda teeters between illusion and reality. In her attempt to escape from the brutal reality of her approaching old age and her daughter's delicacy and inability to enter a social environment, Amanda lives "vitally in her illusions" as Williams, the playwright comments, and is, thus, unstable.
Amanda retreats from her constant nagging of Tom and her expectations of gentleman callers for Laura who is not equipped for the romantic role into which her mother casts her by retelling of stories of her youth and the gentlemen callers she herself has had. In her failure to face life as it is, Amanda runs off Tom and stifles her delicate daughter.
One of Amanda's illusions is her refusal to acknowledge Laura's disability. This illusion of Amanda sustains her in her troubled life to the end of the play as she is seen in "dignity and tragic beauty" comforting Laura, who lifts her head and smiles at Amanda. And, although this retreat into illusions is unrealistic, it is what sustains the troubled characters of "The Glass Menagerie."
I don't think that Amanda's expectations are absurd fantasies, she is a mother who, like many parents, wants her children to have a better life than she did. She does not want her children to have to suffer the way she did, choosing a charming man, marrying him, only to be abandoned with two children to raise on her own.
Amanda is more stable then first appears. She did struggle and raise her children alone, she has managed to keep a home together for them, in a time when government assistance, food stamps and welfare did not exist. Amanda is a survivor, she is smart, and resourceful. She is very brave, having to live like a widow, but with a stigma, her husband did not die, she was abandoned.
Amanda escapes the confines of her life by slipping into her memories and thinking about the days when she was a girl in Blue Mountain and was popular with lots of young gentleman seeking her hand in marriage. The reader does not know if her memories are real or imagined, I think they are real, just a little exaggerated.
Amanda's desire for her children is logical and rational. She recognizes that Tom wants to find adventure, she understands that he wants to live his own life, free from the burden of caring for his mother and sister. She makes a deal with him, find Laura a husband, then you can leave. Her desire for Laura to have a stable future is very understandable, it is quite normal for a mother to want a daughter to get married, have a family, a home of her own.