I'm so sorry she is going through this. Has she been seen by a rheumatologist? She could be suffering from lupus or psoriatic arthritis, both of which can affect the skin and joints. Please check out arthritis.org or mayoclinic.org to find information and symptoms.
Some people with auto-immune diseases are what's called "sero-negative", which means nothing ever shows up in their blood tests even though they have all the physical symptoms. Any doctor who goes only by "the numbers" in a blood test is not worth their medical license. A good rheumatologist will look at a broad range of evidence, including blood work, x rays and other scans, and most important, laying hands and eyes on all of her sore joints.
Pain is a huge factor in depression - please get her into counseling right away, especially if she is talking about ending her life. Don't wait. I've been where she is, and please tell her from me that suicide is a permanent solution to a temporary crisis, and it leaves behind more pain than she could ever imagine. If you have to, call the suicide hotline for advice. [[hug]]
Please tell her not to give up....I have been there....I have a diagnosis of "undifferentiated arthritis", suspicious for seronegative RA or systemic lupus erythematosus (since I also had skin rash induced by the sun a while ago)...my only blood abnormality has been a highly positive ANA (1:640)...I had some swelling of the fingers, hands, and wrists initially, but it's been mostly joint pain & stiffness over the past year...I was fortunate to have rheumies who took my joint pain & stiffness seriously and have been treating me...it's been a year and 3 months since it started but we have finally found a pretty good combo of meds that are working to minimize the pain & stiffness...it takes enormous patience, courage, and time, especially since each med took weeks to months to take effect (or fail as some did in my case)...I've also suffered the mental toll of not knowing what chronic, painful autoimmune connective tissue disease I have....it was very difficult to make it through the past year, but somehow I did...there are some meds that could help her ...find a rheumy who will treat her joint pain...even without a definitive diagnosis, Rx NSAIDs could help (celebrex has worked well for me) and the TCA Elavil has helped relieve my chronic pain (low doses for insomnia & pain)...a mental health therapist who specializes in treating people with chronic pain illnesses can help along with a support group if/when they can give her some ideas of what she might have...I attend the lupus support group even though my diagnosis is technically "undifferentiated arthritis" with lupus-like symptoms...everyone can relate to what she is going through at any of the chronic pain support groups that can be found thru the arthritis foundation or lupus foundation...please make sure her family & friends are there for her...I have lost friends since getting my illness because they couldn't handle losing the old energetic always positive person I used to be...and couldn't relate to what my new " normal" is like living with chronic joint pain & fatigue...but I've strengthened and formed new friendships too...please keep the faith, continue the good rheumy search, and press them to treat her symptoms, not ignore or dismiss them...good luck!!! Please keep us posted too....