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.