There's always a chance she'll quit, but all I know is that every person I know who has claimed quitting has not. Sure, it may be reduced, but from "I'm done with smokes", it turns out to be "Well, I still smoke when I drink or only a butt a day... no biggie". Yeah right.
Just like how some overweight people I know hate that they are big, yet claim they work out and eat much better. Yet somehow they still haven't changed in years. "My metabolism is slow". Yeah right. I bet hardly any work out or eat better. And for all the salads and soup they eat for lunch at work, it must get countered with big greasy dinners and midnight snacking which nobody sees except them.