My goodness, you poor thing, you really have a list of health issues. Gosh. Well, I would start by taking a good, food grade, multi-vitamin/mineral supplement. Extra Calcium and Vitamin are good studies show that almost everyone is deficient in this vitamin, I am, I take 5000IU a day via a liquid preparation. This, with the calcium and good supplements might help your bone issues and other issues such as the palpitations, depression, headache and bone pain. Has he prescribed a DEXA Scan for you. This is a bone scan x-ray that will show just how serious your Vitamin D deficiency is and also calcium deficiency. It takes a little over an hour. I would ask him for one if he has not done this, otherwise, he is just guessing as to what it wrong, blood work is great, but, having pictures is better.
Also, after these tests are done, and you both know more, I would see a good, chiropractor, they can sometimes help with the headaches, insomnia, palpitations, etc. When I have these problems, I see mine, and I usually am better afterwords. They also help with depression and the bone ache as well. However, I would get the DEXA Scan before you do anything else and also start the vitamins/minerals.