The trackmarks fade, but scar tissue remains. Depends on how much scarring whether it is just there or truly awful forever. Which brings up the next question, everything else is like the tracks. If you have a LOT of legal history it's going to stay, none, then that's ok. If you have a lot of debt, family trouble, chronic viral infections, etc, they will fade in time but they are not going to ever totally go away--if you don't have that much, then it isn't that bad of an issue. Also, once you stop, you don't get MORE of any of them.
Then, on quitting,
suboxone or perhaps
http://www.yardbird.com/william_s_burroughs_deposition.htm
He says it best. That is ONE part.
Another part is realizing the mental quirks that keep someone hooked:
1) it is before thought and thinking good thoughts will not work on addiction BUT getting immediate BAD/fear/aversive thoughts on top of compulsions will work.
2) 12 step programs are effective.
3) suboxone can be very effective by allowing a safe context to see how ones addiction works.