对最后两行，我的理解是

In me she has drowned a young girl, and in me an old woman

        Rises toward her day after day, like a terrible fish.

 

”她”作为湖，象镜子一样反射了女人。年轻的女孩形象已淹没，取而代之的是日渐衰老的容颜，就象一条糟糕的鱼。