What's the point of labeling ourselves? So that we can be treated. A patient with cancer worries, and may get depressed, or may even give up - none of those are good for his health, or his long-term prognosis. Yet, he needs to know his condition, so he can treat his disease.
The problem with claiming that we're not addicts is that we can continue to fall into the same old patterns, never noticing the trap. As soon as we accept that we are (or at least, we could be) addicts, we open ourselves up to hearing about all the traps of addiction.
Your question about lashon hora, etc, is a good one, and we can discuss that over a few beers, sometime. For now, though, it's just a distraction. It's only now, after months of being clean, that I can finally accept and realize just how compulsive some of my behaviors were. Whether or not lashon hora has that same issue is irrelevant.
Interestingly, there is no psychological diagnosis of "addiction." There is, however, a diagnosis of "substance dependence" and "substance abuse." Although those are talking about physical drugs, check them up in the DSM-IV (the book psychologists use to diagnose patients), and you'll find that most people here fit those criteria, or at least come close to it.
So yes, I'd say that we're addicts. The idea being, that we have an allergy, and the reaction will be bad if we come in contact. We could get sick, end up in jail, ruin our lives, even die. Especially die, perhaps, because if we don't get free, we'll be trapped and continue to destroy our lives until...we die, stuck in the dirt.
Or, we can choose to break free, something we can do. Powerless doesn't mean we have no choice. What it does mean is open to discussion, but I understand it to mean that I can't put myself in situations where I need to trust myself. I can't assume that I have control.