It's probably because the stories you post either aren't interesting, controversial, or about sex. I've noticed that the stories about sex get the most comments since about 90% of the people here are perverts(that includes women, so don't accuse me of being skybird). You can, however, encourage comments by stating at the end of your post "comments please" other than that, I don't know what to tell you.

If someone has already commented the same way I feel about the post I won't comment, it's already been said.

just not about teenage love and i'll comment. jerk.

Same thing happened to me on my stories
http://isitnormal.com/normal-story-1330.htm
AND
http://isitnormal.com/normal-story-1265.htm
AHEM. Hint, hint. I think this was because it didn't stay on the newest list it got transferred to another so not many people have seen it.
As for people not commenting on yours, write something remotely interesting for a change instead of just being a dickweed. Or maybe you could comment on your OWN stories
EX: "That's such a kickass story. Are you single?"
EX2: "Damn, you sound sexy."
EX3: "You are the supreme overlord of the universe and I prostrate myself before you in humble servitude."

It's not the number of comments you get, it's if any of the comments help or not. It's true, the topic has a lot to do with it. There are people that will place their 'normal' vote but not comment. Look at that percentage of normal votes and there you will find your answer. This post rates at 75% normal so don't fret.
I posted a story in July called 'Mum with Alzheimers'. I was having a difficult time dealing and felt very down. I got two, count 'em 2 comments. Those two comments were sincere and helpful to me. Those two people made me feel a little bit better at that time and made me think. On top of that, my post turned out 92% normal so I got what I needed. My Mum died in August and those votes/comments still have their value.

Give your story with a title that grabs attention, titkes such as boobs, operation, help with the.... You know stuff like that.

Here's a comment.