Hi Stephanie,
about all any of us here can do is stand by and lend a shoulder when we can for you to lean on. It is ok to feel as you do, it is all the part of a process that we have either have been thru or going thru, you are not alone. The one good thing I would like to point out is at least your dr has not given up on finding out what the problem is. Now a days so many drs are in the mode if they can't fix you in short order then they are done with you. So, try as hard as it may sound and go along with your dr in searching for the badly needed answers. Many of us have had to advocate for the care we have received and that can be a tough one to deal with. Depression is part of CP, they seem to go hand in hand. Many times if the depression is brought under control we sometimes see a bit of a decrease in the pain levels. Coming here and letting out your frustration is a good thing to do don't keep it bottled up inside.
I know I have no answers for you, but I want you to know that you are not alone in this mess, you have many people in the same shoes as you are wearing. As Chutz suggested many times a good teaching hospital can be an avenue to explore. But, I would still see what my own personal dr has in mind considering this dr knows your history very well.
Methadone can be a very good pain reliever, but please, please educate yourself about it. If you will do a search here at the forum for Methadone you will find very valuable information on this drug and I hope that you will read it.
Take care and keep posting.