The following post will touch upon the topics presented in the poem when I have fears that I may cease to be of Coleridge.
The first theme existing in the poem is the transient and superfluous of life. Here the author is expressing his disappointment with the world he is living. He knows he will not be remembered, that all his existence will not be more than a remembrance is someone’s mind. He will not endure and the wind will take his last breath and all his life without anyone who remembers him. That is why he has fears the he ceases to be who he is now.
Another aspect within this poem is the pity he feels about not being remembered by his lover. He will not be able to look his lover’s face again and she will not remember him because his life is fading like sunlight in the twilight hour.
One last element of this poem is the author’s awareness of the human feelings fragility when death comes. He know that when he dies, everything in what he believed, he loved, he thought will vanish with his last heart beat. That is why he witnesses when love and fame in the nothingness sink.