I would think that if you got off the coke habit and got stabilized you would not have a problem getting off the welbutrin too. I personally would not want to take a pharmaceutical all my life, they all have side effects. If you do decide to try quitting it, be sure to taper off slowly. You may be addicted to the wellbutrin by now.
I used to take various things but i prefer natural herbs now. I take st john's for low moods, pot to help me sleep and other herbs, amino acids, vitamins, etc for health.