Answer:
The woman sees herself as a terrible fish because her younger self is drowning and disappearing as she is getting older. Which is why this is a great form of imagery because the reader can see a terrible fish drowning just like her younger self is drowning in her new body. I believe that she chose to compare herself to a fish because she feels that she is aging fast and ultimately nearing death.
Explanation:
The woman sees herself as a terrible fish because her younger self is drowning and disappearing as she is getting older. Which is why this is a great form of imagery because the reader can see a terrible fish drowning just like her younger self is drowning in her new body. I believe that she chose to compare herself to a fish because she feels that she is aging fast and ultimately nearing death.
The mirror explains, in the final lines, "In me she has drowned a young girl, and in me an old woman / Rises toward her day after day, like a terrible fish."
The woman was said to have awatched as her youth slowly disappear or fade over the years of looking into the same mirror, which is why the mirror interprets that as a kind of "drowning" of the woman's youth. While te "terrible fish," then, is the specter of old age, the total loss of youth and vitality.