Hey i suffer from really bad anxiety disorders. From my personal experience...
I used to be a chronic smoker. I wouldnt even have time for cigerettes, it would only be joints. From the first joint i smoked (14, im 21 now), i liked it. Within in the next 6months, that was it, there was no stopping me.
Becoz i smoked at ALL the time, i never realised the efffect it had on my anxiety becoz i was never without it. But last summer when i gave up all drugs for 63 days and then smoked a joint (not going into details how i started drugs again) my anxiety was awful and the paronoia was unbearable; so bad i had to go home coz i was freeked out!
From that day i realised the effect joints had on my anxiety. Now i cannot smoke it around anyone, even myself, without increasing my anxiety levels and the symptoms that comes with that.
Now, on the other hand, there are people who claim it helps there anxiety and strongly agrue this point, but i dont see how this is true from my personal experience of when i stopped and then smoked again.
Basically i never knew what the effect on me was until i stopped. Now i know the effect on me and there is NO WAY it would help my anxiety...only make it worse.
Think about how much and how often she smokes it and see if her stopping for a bit may help her to realise its actully doing no good; the way i found out
Hope my story helps