Aspartame addiction?

I ran across this link and started wondering if this is really a problem? It is making me consider my own consumption of diet sodas. I know there is a lot of info out there about how dangerous Aspartame is (and other info that says it is perfectly safe), but I have been trying to cut back on my diet soda consumption and it has been really hard.

At first I thought it was the caffeine I was missing, but switching from Regular Diet Pepsi to caffeine-free diet Pepsi was no big deal. Trying to drink water instead was harder. I can force myself to take water instead of a diet soda, but I would rather grab a soda. Is that addiction to Aspartame? And are there any diet colas available that do not contain Aspartame?