Hi,
I was really unsure whether to reply to this post, just because it's hard to know how you're going to be interpreted.
I was a smoker when I fell pregnant the first time, but managed to cut down to only a few a week (not important).
The thing that worked for me was a change in mindset. I had to stop viewing a cig as a reward (you finished your task, now go outside and light up, you got through that stressful situation, step out and spark...) - Esp at work, but even at home if I knew noone would find out and I'd struggled to get B to sleep, that was my prize.
Instead I would go to the coffee shop next door and have a hot choc instead, or, when I was at home, I decided to knit the baby a welcoming blanket. If I really wanted a fag I had to knit 3 rows first (and go outside to have it). They say the craving takes 15 mins to pass, so if you can keep busy for that time (but promise yourself that if you really want it after that then you can) it may be enough to get you through.
This time around I had my last cig the day I found out I was pg (there was only 1 in the pack and I just didn't buy any more, decided it was not negotiable - easier to do since I wasn't smoking regularly any more) and only had another a couple of weeks ago. Luckily I didn't like it.
I wish you lots of luck, I know you can do it, just don't beat yourself up in the mean time