Really sorry to hear about your friend and the impact it is having on you.   It is impossible to say here what is "wrong".  I could advise all sorts of nutritional/herbal supplements or bach flower remedies, however, in her best interests I would urge her to see a Kinesiologist who will treat her on all levels - emotional, chemical, structural/physical and electrical. 

To find one near you go to www.systematic-kinesiology.co.uk if you are in the UK.  My own website also provides information about kinesiology www.lindabelcherhealthcare.co.uk

I wish you both well.  She is lucky to have a good friend.