First thing that comes to mind is that there should be a separation between the first and second stanza (I would think after "in life")
And I reread the last line, because it does seem a bit different from the rest of the piece, but I think it does its work. The piece in main describes the ferocity of the outlet for pain, but then toward the end, with the line " rage to lash out at the darkness", gives another picture, one of someone who is confused, and the pain is letting through, sort of taking over your senses, so that when you try to defeat it, your only hurting yourself, because inevitably, it IS part of you.
Wow! This sounds like one of my brothers poems. Its really really deep, that it wooshes over my head, which is totally a complinment, cause I have a dulling mind and I tend to not get alot of things, and normaly, if I don't understand a poem, its a good thing, cause its just so good, that its past my years. So you must have done supper, I think I am going to show my brother this poem even, I think he will like it. I really like the words, and how they flow together when you read them. you have true talent.