Hi @criley2k. First of all, I'm so sorry that you have been dealing with this for so long. I know how you feel! It's been 7 years for me since it all began. I find it strange that your muscles are weak from the breathing condition. I wonder if there is something else going on that's causing all of this (breathing + muscle weakness). With all of the doctors you've seen, I assume they've done a bunch of tests that show everything normal.
My respiration has not reset to normal, but it has been somewhat stable for the past 2 years or so. I still struggle with the air hunger, but it's not as bad it was when it started. I do moderate daily exercise which includes about a 2 mile walk and then moderate weight lifting. These seem to help keep it stable. I also do "maintenance" Buteyko exercises about every other day (I do Steps in the morning). I have stopped measuring my CP because, like you, I couldn't really get it up and keep it that way. So I just make sure I can do 90 – 100 steps and if it gets to where I can do 90 and no more, I increase frequency to daily and that seems to get the Steps score up to around 100 after a few days. So that's how I maintain Buteyko. It doesn't help enough for me to do it daily or more than once per day. It provided great relief in the beginning, but like you experienced, it has since provided diminishing returns.
I am able to do pretty much everything normal – I can function at work just fine with not much thought to my breathing. Sleeping is hit or miss; some nights I can sleep just fine in my bed and others I struggle to breathe so I have to sleep sitting up on the couch. I can do my walking just fine, but weightlifting I'm limited by my air hunger. The harder I push, the stronger the air hunger so I can't push too hard when I do exercise. Cardio is pretty much out. Every now and then I'll do a very light jog if I can handle it, but I use my breathing as a gauge. I don't push it too hard like I used to. That seems to make it worse.
So now, I'm not even sure that it's "hyperventilation". I really feel like I don't hyperventilate. In observing my own breathing, it is very normal. It's just that the air hunger starts to creep in after a few breaths, regardless of how fast or slow I'm breathing. So something, in my opinion, is causing this feeling of persistent air hunger that nobody can put their finger on. My hunch is that it could be gastro related. Many of us on this forum seem to have some sort of GI issues. Though correlation does not equal causation, I can't ignore the number of people that have what we have also have GI issues.
So that's where I am today. It's tolerable and stable, but still a bit uncomfortable. It's been this way for a couple of years. Your natural remedies are very interesting. Same thing happened to me when I took vitamin B12 and iron, as I'm sure you read in the OP. Don't know why it would've helped for a short while, then come right back.
Keep in touch, I'd like to know of any progress and I'll share any of mine as I continue to search for answers.