It is important that her anxiety is addressed. It may well be the reason that she continues to smoke. There are usually underlying reasons and sources that cause the symptoms of anxiety. What she is doing by smoking is "self-medicating" her anxiety.
Since smoking is so detrimental to her overall health it is important that her anxiety be address in some other way - be it therapy or medication while talk therapy is taking place. Good luck to her.
She does have ashma but not severe, which I suppose runs in the family, did not realise, she also has severe anxiety could that give her a more possible risk of getting anything serious?
As long as she does not have lung related problems such as asthma and she quits now, all the adverse effects of smoking should dissipate within a few years. If she does not quit she will eventually notice increased aging of her skin relative to her non-smoking friends, increased chance of getting lung,oral and other cancers later in life and multiple respiratory problems.
Even if nothing "runs in her family", it does not mean it will not affect her. Women who smoke and get pregnant also affect their unborn babies and being a young woman she always has to consider that as a future possibility. There is nothing beneficial about cigarette smoking. Why start and destroy the precious body that you are given?