I have to agree with the article. I have experienced the withdrawal symptoms that are listed in the article when I have not had my diet coke for a couple of days. I will admit that I have cut way back. I limit myself to 1 12oz can a day but can't seem to give it up entirely. I have been substituting unsweetened decaffeinated ice tea in the afternoon.
I'm in the same boat. Every time I try to stop drinking diet coke the headaches keep me from giving it up entirely! I'm also trying to cut back though. Good luck!