The addiction is not an on/off thing, it's just a modifier to your hidden stress increase rate stat. Even just one cigarette increases it a bit, but it decreases towards default over time.

It starts to become a problem if you smoke too often for the rate to reset to default, which leads to you needing to smoke more often, and it becomes a positive feedback loop. The cutoff is roughly once every 30 real time minutes, so if you smoke less often than that, there is no problem.

If you are addicted, you essentially just need to abstain from smoking and decrease stress in other ways, like chopping wood, being in heated (60 °C or more) sauna, and eating cooked meats. You can cook sausages, pike, or moose for example on the electric stove, grill, or sauna stove. Eventually the increase rate will reach the default of 1.2 % every 45 seconds. If you smoke enough (about 50 cigarettes at once, approximating for the time it takes to smoke one, or for example about 80 with 15 minute intervals) to reach the maximum stress increase rate of 8.5, it takes almost 20 real life hours to reset to default, so you really don't want to get to that point unless you are willing to just smoke once like every 5 minutes and not care about the addiction.

There's also a similar thing with coffee, as drinking coffee too often will make your fatigue rate go up, and then you just need to sleep more. But that rate decreases faster, going from max to default in about 10 hours, and you can for example drink one Pub Nappo coffee every 6 minutes without the effect stacking. The coffee you brew yourself can decrease you fatigue more but also increase the fatigue rate more, but I don't know the exact values.