First of all, you are a talented writer. I can tell that you have read a lot of poetry; I see the influence of Poe, Tennyson, and other romantic poets in this poem. But you still have not yet found your true voice.
This poem uses some 19th Century phrases, such as "unto" in the third stanza. Also there are a number of cliches: "my dying days", "your beating heart".
I don't know what the poem is about. There is a lot of darkness, but what is the point of the darkness? The poem seems to be about a lost love, but who is lost or who is dying? The whole sentiment of the poem is very 19th Century, and speaks of another, bygone era.
If there is some genuine experience behind the writing of the poem, then it would be good to write about it without such maudlin sentiment. You need to come into the mid-20th Century at least. When writing about personal experiences, don't be naive or sentimental or self-pitying. I think the best thing you could do with this poem is to hold onto a few of your favorite, most meaningful images and trash the rest, then write genuinely from the heart in prose about what happened. Then build a poem on that.
You are talented and have a lot of potential as a writer. Please don't stop.
Namaste