There has never been a substance that someone was addicted and didn't overcome the addiction. From my research on addiction it all boiled down to the addict wanting to stop the addiction more than wanting to continue the addiction.
I suggest that you determine if pre-workout caffiene is more important than being a slave to a chemical. If the caffiene is more important at this point in your life continue using it. However, if you decide that it is more important to be free from addiction, then stop using it and soldier on thru the workouts for the week or two that you experience withdrawal symptoms.
In addition to building muscle, you'll build character.
I kind of agree with Mike on the caffeine. I drink 1 to 2 cups of unsweetend black tea (sometimes with heavy cream) a day, and I don't see it as a problem.
But there is a difference, like Pete mentioned. There's drinking a cup of home-brewed organic coffee with heavy cream, slowly and thoughtfully, enjoying it for what it is and enjoying the effects and benefits. Then there's slamming down 2 or 4 industrially produced caffeine pills made from who-knows-what, sitting around impatiently waiting for them to kick in so you can "motivate" yourself to go to the gym.
It can be a slippery slope, but if you don't feel like going to the gym today, don't go! Make it up tomorrow or the next day.
As far as the supplements go, what are you taking?
Are you working out in the morning? If so, it may be that you are subconciously using the caffeine to wake up rather than to work out. Try working out at different times. You may find that you have more energy in the afternoon and you dont even need the caffeine. Also, try working out to music. Music is a powerful motivational tool
I used to have the same problem. I'd whack down a couple ephedrine tablets with a cup of coffee to get up for the gym. Bad news. And remember Ultimate Orange? I was on that for a while too.
I've found that, when I'm unmotivated for the gym, doing a warm-up at home ramps up the central nervous system and gets you going. It really works. Just do a mini circuit of a low number of push-ups, some walking lunges, squat jumps, etc. Just enough to get your heart going a little, it shouldn't even be enough reps to burn.
It'll cause the CNS to prepare itself for work. I don't take anything before workouts anymore. Let's face it, there's nothing like stimulants, but the little warm up really does work well.
I wouldn't worry about it. Caffeine has helped me get out the door in the days when I was doing a lot of running, and these days it usually helps me have a more intense weight workout. If it helps me get one more rep on each set, I'll get stronger, faster. I don't see that as a problem. :-)
I have a morning espresso, and one before workouts.