At the risk of being off topic, for many years I tried to give up, and found the biggest aid was... Change of Lifestyle.
Drink bitter not lager, or vice versa, use the lounge not the snug. eat sarnies not pot noodle, etc.
Smoking will then only be 1 factor among many, and more easily dealt with.
I was in Germany on business for 6 months, and despite it being the last bastion of the unrepentant smoker, I was done after a few weeks.
Oh, and BTW, dont tell yourself you are giving up, that is a psycho-hurdle, you are only stopping for a while.... just make it an extra day every 24 hrs. You can smoke whenever you want, but you choose not to
Backsliding? not the end of the world - try again, and dont wait to finish the pack - bin them now, or if that is too painful give them to someone else. GFI