I'm not really talking about cigarettes

What is there to say, really. Oops? I'm sorry? Oh, lookie there, I messed it up again?

I wonder...how do you know when you've really, truly beaten a habit or addiction?
Say you smoke cigarettes. Say you're addicted-- you've smoked for years and you can't go more than a few hours without lighting up. How do you know when you're free of that?

The obvious answer is, of course, when you have stopped smoking and no longer crave it. Sometimes habits like that are easier to break when you've made a big change in your life. Not always-- maybe not often, but since this is my hypothetical situation I can make it as unrealistic or improbable as I darn well please. So say you move-- start a new job in a new place and decide to kick the cancer sticks to the curb once and for all. And you do it. You stop smoking-- you don't even want to smoke anymore. The idea of it bores you, even makes you a little nauseated. And you're fine. You thank God for it (because this hypothetical smoker is a Christian, of course) because this was not an easy or short-lived battle.

Then you go visit your friends from your old job. Lovely people, good memories, a lot of traditions and histories. And without even thinking about it, you buy a pack of Camels and light up. Force of habit. When you're in this place, with these people, you smoke. It's what you do. It's how you relieve stress. You don't really even realize you're inhaling til you hear yourself coughing and you're staring at a half-full ashtray and the room is slightly hazy. You are in fact so numbed and so dulled by the normalcy, by the familiarity, of your surroundings that a large part of you doesn't even care that, oh, let's say, six months of freedom has been reneged.

Where are you then?
Are you still addicted? Are you simply fallen for the time being? Does this mean that you should just avoid those old friends who remain such a large part of your life? Is it them? Are you a complete failure? Was the past half-year a complete loss just because you lit up? Because you weren't prepared for the power of habit and familiarity? Because you didn't realize what you'd be walking right into when you went back?
How does one prepare for such a situation anyway?

Were you ever really free to begin with? Did those six months really count as freedom; do you annul your victory as soon as the lighter meets the tip?

I really need to know.