They grounded me for three months and made me chew and swallow a whole pack of cigarettes. I'm polite about my habit. I take it outside and don't do it in front of my parents.
How do I get them to understand?
Your parents making you chew and swallow a pack of cigarettes shows their desperation and total lack of understanding about this addiction. They are punishing you for something you need a lot of help to stop. Usually people stop and start up smoking again three times before they quit for good.
Your parents need to have your addiction explained to them by a health professional, perhaps your pediatrician or family doctor. The American Lung Association and the American Cancer Society, along with many other local (and regional programs and probably the HMO you parents might belong to) have stop-smoking and support groups in your area. Please contact your doctor and speak with her first about talking to your parents. Then take the courageous step to quit and enlist the support of as many family and friends as you can to help you. If you think that your parents would listen to me, have them email me and I will explain the situation to them.