For me Juju's post hit the nail on the head!
I did exactly that last night when I gave in and had three puff's - I GREW UP - I thought this is how I started as a teenager 21 years ago and I'm not going back to been that teenager again, I passed the cig to my friend and went to the toilet in the pub and beat myself up, felt sick, smelt vile and looked in the mirror and said "Grow up stupid, you don't need a cig you just wanted one as everyone else had one -GROW UP!"
It helped me and I will keep telling myself to grow up if the junkie in me tries again
Joanne