The difference that the poet feels after Lucy dies is that he looks upon his life and surroundings differently. He has a transformed outlook on what life is all about, and when he looks out at the world around him he perceives things differently.
This is immediately apparent in the first poem of this five-poem collection, all under the title “The Lucy Poems” and subsequently sub-titled “Lucy’s Legacy." In the first poem the poet says that the world is bleak since Lucy died. He desires rain to quench "that parched garden." This garden represents his world, which has been parched since Lucy died.
In the second poem of the group, he states that he talks to the environment around him. This is probably something he never did before. This is how his life is now different. He talks to “rocks, and stones, and trees." In talking to them he "hears" Lucy’s deadened voice. It is as if he can still communicate with his beloved Lucy. This must be comforting to him and is his way of dealing with his loss.
In the third short poem of this group, the poet says that is sure Lucy rests peacefully because of the dying roses that he sees. He’s different now because he can be assured by something that in itself is dying—in this case, these roses. He also sees the sea differently, and to him the sea sighs every time he thinks of Lucy. Therefore, he perceives the sea differently than he used to.
In the fourth poem, the man is different because he has lost a child—Lucy. It is tragic when parents outlive their children. The children have not had a chance to live a full life. This man is forever changed and different because of the premature death of Lucy. His dreams for her—to be successful and fulfilled and more—died with her death.
In addition, in the fifth and final poem of the set, the man asks that those who knew Lucy remember her legacy. He does not want her to be forgotten. He is now different in that his focus is on keeping the memory of her alive. Her legacy is what he has to hold onto now. This will be his comfort and it will be what sustains him for as long as he lives.