The first time I read it, it was difficult to understand. But the next time around, I STILL barely got it, but it was forming an image. After about 5 or 6 more readings, I finally got it and was nearly taken aback. Such power, yet such hidden beauty. When you first start, it sounds like it's going to be some beginning to a dirty novel, but then you read it over and over and OVER again. You begin to be appalled. It's odd: you want to keep reading, despite that.
The meaning, to me anyhow, is that a man (judging by the title, the "narrator" is a male) feels like he wants too much of a physical relationship and it makes his significant other (didn't give a gender, so I'll leave it at that) sad, resent-filled, or even just plain angry. Or maybe he was too rough, in a sense? Either way, in the end, it seems to me that the pain becomes too much for him to bear and he feels it necessary to burn the pain away, or simply kill him with the same burning that caused the more physical than emotional relationship.
Even if that's not the original intent, that's how I interpret it. And it made me cringe at first. But then I softened and looked deeper, noticing how much a character like that could be in pain. (that wording might not have been correct)
I have never read a better poem, aside from anything by Robert Frost. Exceptional. I literally have no complaints.