Ok this a very long plan so pay close attention. Have a friend talk to her and keep her busy. While they are doing that go and steal all the real cigarettes and replace them with the water vapor kind. Problem solved. It might take a while but it's simple, safe, effective, and approved. Your welcome.
Take some printout of the patients of oral cancer and paste on the wall of your house and write you are risking your as well our lives by smoking and we become passive smokers more dangerous then the actual smoker.
What things bother them? Just start ruining things for them (they're ruining your air) My aunt died from lung cancer--she never smoked. The doctors said it was a combination of 2nd hand smoke & the emissions from autos (she was an avid runner & lived in the city) When they're trying to watch a show or movie crank up some tunes. Get some nasty perfume & just start spraying like a mad person. Just get on their nerves, go for broke & just start throwing parties etc