Relapsing can be a terrifying experience...all that work of quitting goes down the drain!
Everyone here makes really valid points about starting over, cravings and requitting. Jeniwho, Twiggie - do not let your relapse get you down. It is what it is....a slip...HOWEVER, don't think you can start over and slip again and repeat that cycle without some hard work.
Prepare yourself well for your start over. Read about relapsing. Make yourself really aware that NOTHING improves by having a cigarette. Be prepared to fight through the difficulties in your life without relapsing. Most of us have tried and failed a few times.
Only when you are ready to fight the battle with the Nicodemon and to WIN, will you quit. Nicodemon/the addiction is always lurking in the background of your quit, and it does take quite a long time for you to be able to get through emotional events in your life yet still be able to turn your back on smoking.
We old timers keep saying that the odd crave arrives and we can laugh it off...indeed we can, but we still went through times when it was very hard indeed. Don't set yourself a goal - for example - 'Once I've been quit for 2 or 3 months/years I'll be a non-smoker.
Just take one day at a time and be proud of yourself for that day. Always remember the possibility of relapse and fight it with all your life.
It is your life you are fighting for!
Whatever it takes, just don't smoke!
Love Lolly.