What is an example of symbolism in the story, Your Duck Is My Duck?

In "Your Duck Is My Duck," the narrator's painting "Blue Hill," represents the disposal of and retreat from artistic expression. After the narrator's relationship with Graham ends, she discovers he sells her painting to Ray and Christa. Though the piece was once valuable to the narrator and Graham, its redistribution only succeeds in furthering the narrator's artistic disillusionment. Lost in a cycle of avoidance and numbness, the author struggles to confront the depth of her creative unrest. When the reader learns her painting is now owned by the exploitive and elitist couple, the understands the true significance of their hold on the dimensions of the narrator's world and consciousness.