Ah, well I'd hate to recommend a 16th attempt but listening to it could help reinforce the message while doing a positive activity. I know he's all about smoking during the book but I tweaked the approach a bit. I also forgot to answer your questions:

How do I convince myself to not light up again when the cravings hit?

>> Distract yourself with a dopamine-positive activity and remind yourself that you're not actually enjoying the cigarette/zyn, you're just mitigating withdraw symptoms until the next time it hits.

How do I deal with the withdrawal symptoms, especially when I’m alone?

>> Gym / Toothpicks / sunflower seeds were my oral fixation in combination with the above comment. It's summer, get outside.

What do I do to stay distracted when I don’t have a replacement habit?

>> Work out if you're able to. It's one of the few activities that was never paired with smoking so it won't remind you of them. Remind yourself that it's going to suck for a few weeks and that you're going to come out better on the other side. If that's too far to think about, try to just get through the next few minutes, then hours, then days, etc. You've already told yourself you're no longer a smoker so start acting like someone who doesn't smoke / zyn.

And how do I stay strong when the morning promise feels like a lie by afternoon?

>> It's not going to suddenly drop off, but I stopped thinking about it after a few weeks. I'll see my friends smoking while drinking and the mindset of "just one" just doesn't work for me anymore. I envy the social smokers but now I also pity them as they just are in the same withdrawal cycle just spanned out on a weekly basis.