From what I'm reading, your son has given up hope and that can easily be a big part of why he is depressed. He sees no future and that is sad for anyone but especially for a young man like your son. You alluded to the fact that he blames God, too. I don't believe God gives anyone any of this. It doesn't fit His "MO" (modus operandi). If you have a church family, perhaps the pastor/priest could speak with your son.
I just know that we have to learn how to live with what life dishes out to us. Dwelling on what is happening to our body will only cause more stress and more pain so we shouldn't dwell on it. That will make us more depressed. Instead, we should use our minds to find ways to work around the illness to do the things we want to do. Right now your son is stuck in the "why me" mold and needs to move forward.
It's difficult when doctors really don't understand. I have a wonderful board certified Internist that believes in fibro. There are some great rheumatologists out there, too, but you have to do your homework. They easily could be in your location but you want to make sure they treat fibro patients. Ask before you make the appointment. It's really a slap in the face to be treated like it's all in your head. No it isn't! Your son is in pain and is looking for help. BUT he needs to know there is no magic pill out there, as GSD Girl stated.
We have been raised to believe that doctors can cure us but there are so many things they don't know and can't cure/fix...and fibro is one of them. That's why he has to be an active participant in his feeling better. He needs to WANT to get out of that bed and start living his life. There are things he can do to help with his pain and gentle exercise is one of them. Trying some of the supplements that have been mentioned here could help him, too. He needs to accept the fact that he won't be pain-free but he can have a wonderful life in spite of this illness.
Depression is terrible. I don't suffer from it and have a positive outlook on life. That is a blessing but that's also because I have a lot of hope. I have hope for the future and hope that the doctors will find what is causing this illness and hope that we will find true relief and, better yet, a cure! I did suffer from bad depression when my husband died suddenly and it was horrible. I didn't want to do anything but disappear. But I made myself get up and start functioning and your son needs to do that too.
He should start out slowly if he has basically stayed in bed. Gentle stretching and walking would be the first thing he should do. The more he moves the less the pain will be...but not at first. His muscles will rebel but he needs to keep at it. Pace himself. As he becomes more flexible, the more he will be able to do. That will be the beginning of jump-starting his life. Then he should find something to focus on instead of his pain. I love to do genealogy and when I'm working on that, the pain fades in the background some.
Plan some fun things to do and don't let him say he can't do it. You can do anything you put your mind to! Look at the people who have lifted automobiles off people! If you looked at it you would think you couldn't do it, but it has been done numerous times! God has given us great strength and a wonderful mind, too. We only use a small portion of it! But, you CAN'T do it if you aren't willing to try. That's the kicker. He has to want to try.
So, I would suggest you become a cheerleader! Don't join the pity party. I know your heart is breaking seeing your child hurting like this but you aren't helping him IF you are helping him feel sorry for himself. Getting him motivated and looking forward to each new day is the goal. It can be done.
If you believe what I'm saying and want to talk more, don't hesitate to email me. Just click on the envelope under my name at the left of this post and it will take you to my email. Meanwhile, I'll be praying for your family and especially your son that he will start getting hope back in his life.
Sherrine