I think this line really shows the feelings he had for this person which also shows why he is so tore up with being apart from his love. In one of the lines of the poem, the author uses a metaphor by calling his lost love a "lost discoverer". When I hear this comparison, it makes it seem like he is talking about someone who went out searching for something but never came back. This again brings back from earlier about being lost in the ocean. He uses the ocean as a perfect example of losing something so quickly and easily.
The author is obviously hurt and upset about losing the love of his life, but close to half way through the poem, he expresses that he is working on moving on with his life. "I made the wall of shadow draw back, beyond desire and act, I walked on." (593). These lines are important in this poem because he changes from talking about what she or he has done to him, and directs the line toward himself. When he talks of the wall of shadow, I feel as if he is speaking of the pain he is feeling as well as being abandoned. He then says he made that wall draw back, which seems he is pushing those feelings further away from him which would free him from feeling so down. With the very next lines, I feel as if the author really hints at why he and his lover are no longer together. "Oh flesh, my own flesh, woman whom I loved and lost, I summon you in the moist hour, I raise my song to you." (593). To me, it really seems the author did something along the way, either leaving her or doing something for her to leave him. This point also brings back the main theme of the poem. If he is the reason they are not together anymore, then this is possibly the reason he is so upset and feeling abandoned. Doing something that causes a big change in someone's life could really put them into depression knowing that things could be completely different. .
If we skip a little later in the poem, the author uses a metaphor that proves the point that he has moved on from his lover.