the easy part of giving up is stopping, the hard part is staying stopped.... when you give up something that you enjoy (even if it's bad for you) your life is missing something. the only way you will continue to abstain is for your life to get better because you have given up. i havent read all this thread but it looks like you are well supported. try and find the web-site that has the smoking clock on it; when you give up again start the clock - you then have a running update of the extra time you will live and the money you have saved (if i find it again i will send a link). plan a 10k race for a week or so after your give up date. do something that makes it worth your effort to give up. if you have a lapse, dont panic. in ten years time you wont be smoking, one of the fags has to be the last one.
nicotine withdrawals are bloody great! if there is one good bit of advise i can give you it is, sit back, stop smoking and experience a complete electrification of every atom of your body when the craving starts... i'm sure it took me several attempts to stop just so i could go through the mill one more time. you lucky nearly ex-smoker!
just check out the ingredients, if it's got ASDPARTAME in it i too get headaches (and a host of other nasties). i'm not saying that this ingredient is a problem but i will not buy, eat, drink or use any food product with it in.... i'll get off my horse now and start some running again!