Depression can do it too. It was years before I admitted that, even though the physical symptoms of exhaustion were being treated with thyroid - I had the same as you vivennemme, symptoms but normal blood test - the symptoms still kept coming back. I went the other way too though: I kept going to the doctor saying, 'I can't be depressed, I just started a new business, joined that club, that committee, I'm doing this and doing that and everything was brilliant and now I can't move and I hurt and I'm exhausted and it has to be physical.' The doctors never told me that depression can cause physical symptoms of that kind, but it does. Mind, you'd think they might have smelled a rat or few with what I kept saying about my unexplained and sudden crashes into depression. I've been on medication for bipolar now for about five years and I have my life back. I can get up in the morning, do a days work, relax in the evening, have a good night's sleep (although you wouldn't think it with me typing away here at 1.30 am!!), and get back up the next morning and do it again - every day. I couldn't even think about that a few years ago. I've come off DLA because I can run my own life again and the stars are shining and the birds are singing and I notice them. Oh dear, I'm running away with my thoughts again. Sorry.
I guess I just wanted you to understand that sometimes exhaustion has nothing to do with physical problems and everything to do with mental ones. Depression is very common with diabetes: understandably as we have a lot more to deal with than well people do - and please don't shout at me for saying we're not 'well', if juggling food and injecting insulin and going hypo and trying not to, is well, then whoever says that has pretty low standards or 'well' - oh heck, there I go again.
The other thing that can happen is that whatever physical problem initially caused you to be so exhausted can seem to still be there once the medical side of it is sorted because inactivity and exhaustion themselves encourage depression. There is little more depressing than staying in bed all day and doing nothing, and when you are depressed it is very hard to want to do anything else, so you get into a never ending spiral.
I hope you get sorted, but I think that idea is worth a thought just in case. Good luck.
