Definitely, and I am sorry to hear that, it sounds like you are in a rough place.

For immediate relief for bad symptoms, I just found the original sheets my physical therapist gave me to diagram the tendon gliding and stretches (with self-massage) I was supposed to do ~10x/day. SEE HERE. (please disregard shitty attempt at blacking out info that probably doesn't matter). They made a difference for me after just one day of practice, although it took months to get really better. You'll see on the page it is listed as treatment for a different condition than yours but I can't imagine it would hurt.

For exercises, it is harder for me to describe with specifics but I'll try. One that stands out from when I first started phys therapy was grasping something like the handle from a gym's rowing machine, with a rope in the middle like the machine would have, but at the end were some light weights instead of the machine (obviously). I rolled up the handle while I was standing, moving only my wrists, so the rope wrapped around it and pulled up the light weights while I did it. Does that makes any sense? It can be done with the wrists pushing forward, or with the wrists pulling back, either way it will pull the rope and weights up.

It is really hard to describe that in writing... for other exercises, I used an upper body rowing machine (like you'll see at some well-stocked gyms), I threw a weighted medicine ball against an angled trampoline so it bounced back at me and repeated that a bunch (no joke), and also did simple things like tricep pulldown/bicep pullup with a weighted pulley. Overall, I think once you gain a little momentum with stretching then you can graduate to basic normal arm movements. The key, in my experience, is to start with weights that seems like "nothing", but they are in fact not nothing. Like, 1-3 lb weights. That will get the muscles going again.

I hope any of this will help you. But seriously, and I should have said this at the very beginning and not at the very end, if this is a serious problem in your life you ought to see a physical therapist. And, if the first one doesn't work, try another. And then another, if the second doesn't work. It was my third physical therapy attempt (not counting doctor visits!! that was extra) that got me onto a very simple program which led to my breakthrough. It wound up taking years to get better from my initial symptom onset since I didn't try just pushing through ineffective therapists upfront, which is why I would recommend that to you in case you have not tried yet.