Dry heaves, nausea, and severe diarrhea - Desperate for Help!

Hi Everyone,
I am looking for help for my mom.  She's been having these severe symptoms for 3 years now and has seen all sorts of doctors, none of which have been a great help.  She's 48 years old and symptoms began very suddenly.  She woke up with what she thought was just the flu, and never went away.  She's lost her job, quit graduate school, and has spent countless months in bed barely able to move.  

Here are her symptoms:
-Dry heaving without vomiting.  This happens most days and persists for sometimes only 15 to 20 minutes or can last for several hours.  She will go through periods (1-2 weeks) and not have this symptom at all or only experience very mild heaves.
-Severe diarrhea.  As gross as it sounds, she describes it as a "pudding" consistency.  She experiences sudden onset and can go 10 or more times in a day.  She has tried over the counter anti-diarrhea medications such as pepto and Imodium (immodium), however they do not help at all.  The only thing that will occasionally firm her stool are the pain pills she sometimes takes for her back/hip.
-Nausea.  Her stomach always hurts.  She has tried over the counter remedies and even taken medications they give to chemo patients for nausea, however they have not helped.  Just today I got her some ginger root tablets (I don't know why we haven't tried that sooner, ginger is a well known natural remedy for nausea!) which she said helped her today, however it's the first time she's tried them and isn't sure if it's coincidental or if they actually worked.
-Nerve pain in her hands. She's had tingling in her hands as well as soreness.  The pain is similar to that of arthritis, and her doctors disagree with whether or not she has rheumatoid arthritis or not.  She doesn't have the disformed joints or some of the markers for RA, and RA drugs didn't help.
-Pain in her hips, knees, and back.  As mentioned before, she has a few slipped discs in her back, which caused sciatica.  We do not think the back pain is related, however she does describe general all over body aches, like the "hit by a truck" feeling you get when you have the flu. We do believe the "flu-like" pain is a symptom.
-Cognitive dysfunction.  She doesn't catch on to things as quickly as she did previously and has a difficult time remembering simple things like to pick up a prescription or when events are.  It takes her far longer to learn new things such as a new technology or task for work.  It's not very severe, however prior to her becoming sick she was in graduate school and a very active learner.
-Sensitivity to cold.  We live in Orlando, FL, and though it has been an unseasonably cold winter both this year and last, she is incredibly sensitive to cold.  Even on days like today when it's pleasant and sunny out (70 degrees or so) she complains she is freezing and will sit under big blankets.  When it get's really cold, like any where in the 60's or below, she's just absolutely miserably cold and has a very hard time warming up.  No fever is present.
-I should mention she was diagnosed about 7 or 8 years ago with interstitial cystitis, which is a bladder disease.  It has been well under control for about 5 years and she no longer takes any medication to treat this.  
-Also, she had a full hysterectomy when she was in her 30's.
-We do not believe these symptoms are related to any sort of anxiety or mental health condition.  She was 45 when these symptoms started and she was not under any unusual stress and happened during an otherwise happy time in life.

She has had pretty much ever test under the sun.  Here are the major ones I can recall.
-HIDA Scan - Showed dysfunction in her bile ducts, however there were no stones present in the gall bladder and no disease found in the gall bladder.  Regardless, she had her gall bladder removed about 2 months after her symptoms first started, so nearly 3 years ago.  The symptoms disappeared for about 6 weeks and then returned.  We recently discovered when one of her doctors asked that they only removed the gall bladder and not the duct work, which was the part that was dysfunctional.  It seems that there was no reason to have the operation.
-Colonoscopy - She's had at least 3 or 4 since her symptoms started, and had a few before any symptoms as a part of routine checkups.  They have all come back negative, with the exception of a few benign polyps.  No bleeding, lesions, or ulcers were detected nor are there any signs of Chron's disease or diverticulitis.  
-Endoscopy - She's had at least 2.  Both were normal with no signs of damage to the esophagus or stomach.
-Capsule endoscopy - She had this done about a month ago, and it came back normal.  The only thing they found were slight peptic ulcers, though her doctor does not believe this to be the cause of her symptoms.
-Stool samples - they tested for all sorts of parasites and fungi, all were negative.
-She has had blood work done consistently and has come back negative for celiac, MS, Hepatitis, and and Sjogren's.  
-She has shown a slight thyroid dysfunction and was put on medication to "rev up" her thyroid, however she has stopped taking the medication because they gave her severe hot flashes and mad her feel worse.  The doctors haven't really said much about her thyroid or anything in the endocrine system.

We are back at square one trying to look for an answer.  Has anyone else experienced these diverse yet puzzling symptoms?  None of her doctors are particularly helpful and we have seen many of them in town during this saga.  She has basically lost her life due to this, and is desperate to get it back.

Currently my top theories are Vitamin B-12 deficiency/pernicious anemia or maybe hypothyroidism.  Her gastro guy doens't seem to think pernicious anemia is a viable option because he claims her B-12 levels are fine, however I have not seen any blood work or lab results indicating she has even had her B-12 levels tested.  Plus, all of the symptoms fit.  As far as the thyroid goes, we just haven't really explored the endocrine system to see if there may be any contributing factors so it may be something to explore.  We are desperate for help and any suggestions are most welcome!  
Thank you!
Kai

[daznchrise]

Hi, sooo sorry to hear about your mom.  I too have had similar symptoms for only 3 months.   I am 54 and feel like I am pregnant, very sleepy, joint pain and hair loss.  I took a blood test and did find out I was very deficient in Vitamin D3.  Will let you know if it helps.  I am taking 5000 units per day.