How does the writer use symbolism to give meaning to the story?

In this feminist tale, the main character is a wife and mother who withdraws from fulfilling her expected role as caretaker and nurturer of others. She feels trapped by the expectations that come with her role. Her right nipple, "shrivelled with chill," symbolizes her inability to nurture, to produce metaphoric milk from her breast, as a mother is supposed to do. She is afraid of the violence of her son's need for her, symbolized by the fact that he pretends to be a tiger and scratches her, making her bleed. His role as a tiger symbolizes that children are, at least to this woman, feral and dangerous, and not the innocent angels of domestic stereotypes. 

Fairytale motifs symbolize her entrapment: the wife is a “cloistered queen” and a “young virgin in a tower.” Being a queen symbolizes power and privilege and virginity symbolizes purity but both these roles are symbolized as prisons, from which the woman is unable to escape. In fact, the women doesn't try to physcially escape: she simply withdraws into her own world within the imprisoned domesticity in which she lives. The "white room," a "girl's" room, also symbolizes virginity and her desire to withdraw into a girlish state. This symbolism works in opposition to her "breast," a symbol of the womanhood she wishes to cast off. 

The color gray symbolizes the woman's depression. For depressed people the world often is dull and gray: here, her child has gray eyes and her husband wears a gray shirt. Underscoring her dismal mood, the story begins in winter, a symbol of bleak times and dying. Also, as the woman gazes out the window, she sees symbols that reinforce her sense of life as dismal and off kilter: a boy can't seem to learn to ride a bike and an old woman "extracts a parcel" from the  trash. The women watches but is alienated from these acts. 

Finally, we see her attempts to nurture as literally killing her: when she prepares a big feast, she dies. Many of the images of her feast are typical symbols of domesticity and nurturing: warm bread, a stuffed turkey, pies, a glazed ham, fresh laundered sheets, but woven in with these are symbols of despair and depression that foreshadow her death: "grey" sweaters and "mad ... stories:"

The man and boy came home and found five loaves of warm bread, a roast stuffed turkey, a glazed ham, three pies of different fillings, eight molds of the boy's favorite custard, two weeks supply of fresh-laundered sheets and shirts and towels, two hand-knitted sweaters (both of the same grey color), a sheath of marvelous watercolor beasts accompanied by mad and fanciful stories nobody could ever make up again, and a tablet full of love sonnets addressed to the man. The house smelled redolently of renewal and spring.

The price of nurturing, the story implies, is death: the woman in caring for others is eaten alive, perhaps symbolized by "the marvelous watercolor beasts" she paints.