Hi Candace,
I am really feeling for you right now, you are in a very scary place inside and no one is listening it feels, but mostly it is because they are frustrated because they do not have answers to help you, give them time and understanding and go easy on yourself most of all.
when i read your post something inside responded to some of the similarities and something that might be worth checking out is rhumatoid arthritis, I know that sounds absolutely crazy but my dad had horrific vertigo, couldnt stay balanced and even passed out and he had no other symptoms at all, just those. he was in hospital for weeks having everything neuro checked out and it was all ok. for some reason they did some other tests and R.A. came up. within months he was told he would be in a wheelchair within 2 yrs as it was agressive. he believed it was auto immune infection and treated himself with the help of a doctor taking massive amts of antibiotics to kill the infection in the joints, that was 18yrs ago he is in his late 60's and playing league tennis and has been in remission for yrs. but it ALL started with vertigo. I know this does not answer all of your questions, but it may be worth looking into if nothing but to rule it out. good luck and god bless. Michelle