I was the person who asked Maddawg about the song. And yes, Guest 999, I'd seen that "confessions of a road-squid" message board thing about six months ago (I'd been looking for the song for a while). Unfortunately, the lady who quoted the stanza hasn't posted on that board for years and I was unable to get in touch with her there.

However, the good news is that I figured out who wrote the song, and once I did that I was able to find it. I was right about it being by someone from Chicago: Richard Lemmon, who wrote the song for the birthday of a friend of his wife who was a serious chocolate lover.

He used to call the song "I'm a Chocoholic," but now prefers the title "Chocoholic Waltz" and as it happens had posted it on YouTube a few months ago. He's also changed the last line of the chorus, he says he thinks people have different associations with "Fanny May" now. Here's the YouTube:
http://youtu.be/hdhzEyMRqgY

Incidentally, if anyone out there DOES have a recording of the early 1980's WFMT broadcast of the song, he would like a copy.