I am not suffering nearly enough to offer you the empathy that you need, but I am sorry for what you are going through. My condition has been worse at times in the past, some days are better than others, but it is an untreatable, degenerative neuropathy, so I do look forward to increasing disability. Right now I can deal with where I am, and hopefully that will continue to be true, wherever that ends up.
Are you and your doctors adequately addressing pain relief? It makes the biggest difference in my quality of life, completely transforming both how much I am able to do and how I feel about myself and my world. I hope that you get a definitive and treatable diagnosis soon, but in the meantime insist that you get some pain medication for breakthrough pain so that you are able to do even a few of the things that bring you joy, without having to regret it.
Hopefully others will have more constructive help to offer. You are certainly facing daunting challenges. How is your support system?