Oh dear Andrew,
It requires willpower to quit (even Zyban) believe me I still get cravings and I still get tough days.
You have to really want to do it. SO you had a few pressurised phone calls, did a cigarette REALLY make you feel better?
Nope.. it wont because its just a temporaray thing, your body is ALWAYS craving nicotine, which is probably why you tried to quit.
I presume you did not prepare and do the workbook located to the left. This will make you think about WHEN you are going to fail, or likely to, BEFORE you do... and therefore you can prepare for it.
I failed loads of times, and had to start again, and again and again...
But honestly I got sick and tired of going back to day 1 over and over again.