Well duh... and no insult intended.

If the lady is a pain slut, "beat" her each and every day she goes without smoking. It's so much easier when you replace the vice with something pleasurable.

Verbal and menial disciplines, as many suggested, are all you should attempt for misbehavior. Cum denial, while fun, is stressful. I'd suggest not doing anything stressful while she is withdrawing from nicotine.

Plenty of orgasms for correct behavior will keep her mind off of things... and give her something nice to suck on as an after sex activity...