With Aftermath, which is still one of my favourite selfmade poems, I made an attempt to express the feelings of a girl whose boyfriend has recently converted to ex-boyfriend. Of course you might as well apply the poem vice versa, but I think it fits more into the "boy left girl" situation. It might be interesting to you that, at the time I wrote that poem, I had not had a girlfriend myself yet.
At first, there was nothing but four lines: all these words / everywhere / it still hurts / you don't care. Over the time (i.e. during a latin lesson :), these lines formed into a larger poem, much alike this one.
But I had put so much focus on the repeating lines and their rhyming counterparts at the end of the verse, I simply didn't care about any more rhyming. When I finally read the text in front of me, I noticed that the missing rhymes made the poem sound much less "rounded up" as it could.
So, I did my best to make the other lines rhyme as well while still retaining the original meanings of the sentences as much as possible. As well, I added a fourth and fifth verse, and the result was exactly this poem.