What you describe, sounds so horrible. It must be so frustrating trying so many things and have no solution. Has she tried herbal therapy? Does she have access to a medical professional that could help her with herbs?
Many years ago, when I was extremely sick, I experimented with many herbs and found a combination that worked for me. As I had written in the past, I do not encourage people to experiment like I did, for there were sometimes my "natural" experiments backfired where I felt like I was dying (these were anti-mercury supplements, rather than herb teas). But the end result with my many experiments is that I'm well today. I used to make batches of herb tea every three days, from bulk herbs and take it in great quantities.
I took these herbs because doctors could not find anything wrong with me (eventually I had my mercury-silver dental amalgams removed and I'm a different healthy person today - but that's another long story). Herbal therapy if done correctly is a very slow process and can help some people get well. I am one of those people. I took notes, so that I could determine my progress. As long as I could honestly say I was getting better, I continued.
The interesting thing about herbs is that they can help you without knowing exactly what the problem is. Herbs are foods that assist the body in healing itself. Some might suggest herbal combinations, so that you cover a wide base. Herbal therapy must be in conjunction with a healthy diet (that she can tolerate obviously) and other positive lifestyle changes.
As far as I know, most MD doctors know little about herbal treatments, in the United States, but I hope that your friend might find a medical professional to help her with this. One must do a lot of research here before trying to use this kind of therapy. It's not like you sprinkle a bunch of herb tea leaves in a cup of hot water, and then expect to get immediately better. It's a delicate science. I based my success on anecdotal evidence, through much experimentation. I only did this on my own, because I had no-one that I knew that could help me.
A very long story short: About 23 years ago I was told by a doctor to not run more than a hundred yards and today I run about 19.5 miles a week (plus many additional miles of hiking and walking at times). I still take a very small amount of herbal tea in combination for good health. I noticed even recently that this herbal tea does help me run better. I even look about 20 years younger than my actual 51 years of age. I contribute that a lot to my struggle with my illness (fibromylagia symptoms, among others) in which I defeated it through natural means; removing toxins, improved diet, exercise, and herbs.
I hope that your friend can discover the same. It took me many many years to find the solution that best fit me. For your friend, I don't think that it will be easy. But I hope that she never gives up. Keep trying (including prayer if you so believe like I do). I wish your friend the best.