I know a doctor who has done extensive research on why people use drugs and he has come to the conclusion that most regular drug use (tobacco included) is for reasons which basically come down to anxiety. People choose their own form of Valium to help tranquilize themselves. Some people choose alcohol, some choose tobacco, some choose illegal drugs but the doctor thinks the root cause is the same.
Tobacco can be the hardest drug to quit. People who quit often feel cravings (anxiety) months after quitting. Heroin treatment programs will try to keep their clients off of heroin but usually make no attempt to control tobacco use because they regard it as hopeless. (Ironically, tobacco kills a greater percentage of its users than heroin does.)
Doctors who specialize in addiction treatment say that the only method that works for the majority of people is drug substitution. That is, taking another drug in place of the current one -- the nicotine patch, for example. That method will generally work for the majority of people whereas other approaches -- like going cold turkey -- will have a success rate of about five percent per year. That's because simply stopping the taking of the drug doesn't address the reasons you started in the first place.
If you are really serious about quitting, you might look into ibogaine. Many people have reported that a single treatment cured them of their drug addictions.
It is all highly individual, of course, so whatever anyone else says you will have to experiment and find what works for you.