AAYATUL KURSI is THE best solution. It is THE greatest ayah of the greatest and most blessed book of the Creator of the universe (which includes jinns!!). The amount of Ahadith stating its significance and its power are uncountable. maybe a learned person can write down a few. Just tell her to read it in the morning and in the evening, and also to read the last three surahs of the quran and blow on herself. this whole procedure shud be done thrice (this is also from the hadith). And obviously, keep making dua to Allah Ta'ala for help. Trust me, it wil work, Insha Allah. wassalam.