Sorry to hear you're having issues. Is this from a comment on the AC blog? If so, in theory (and that's how it's been working for me all the time) it only sends you an e-mail if you subscribed (when you reply, tick on or off the 'notify me if someone replies to my comment') to the replies, and only if someone replies to your comment or to a reply within your comment. Even so, there should be a link in the e-mail to remove you from it (it says "You can stop receiving emails when someone replies to this post, by going to (link)").
If it's a comment on the forums, then you can unsubscribe using the THREAD TOOLS at the top of your thread. There should also be a couple links to unsubscribe from the thread or from all threads in the e-mail you get.