Hi, Roxie. First, I don't know the ends and outs of your endo issues and I am not in the medical field, unless you count a first aid course I took. long ago.

I have some questions about your sleep apnea. OSA, can make many of our symptoms worse. I have no idea if the following pertains to you but just in case it's impacting some of your symptoms, I want to post this information. If you already know it, it might help someone else.
Are you currently on a cpap/apap? I know compliance is difficult, been there, done that, but being on the cpap has made my symptoms better, relatively speaking. As my sleep neurologist so aptly puts it, I still have the damn fibro and the comorbid conditions that come with it. Sleep as we all know, is so closely tied to how we feel. IMPO we should all have a sleep study, but I'll save that for another post.
The areas where I have noticed a difference are a decrease in morning depression and achiness, not as foggy and no morning headache as well as more energy during the day. Again relatively speaking. I take Nuvigil, which many people with sleep apnea take for daytime sleepiness. It does not hype me up, although caffeine does, and works most of the time. It makes me feel closer to normal, if that makes sense. I have also been known to take it and then sleep for another six hours, so I can imagine I would have slept longer without it. Since I am up for longer periods during the day, this makes it easier for me to fall asleep and stay asleep at night.
In my case, I had no idea my breathing stopped 51 times per hour for ten seconds or more. No idea. Any apnea events over five per hour means you need to be treated. There are a lot of myths about sleep apnea such as you have to be overweight and while it's a risk factor, the majority of people with OSA are not obese. Some people don't even snore. OSA is structural and as you get older (not old) the muscles in your tongue become more lax and may end up blocking air from getting into your lungs, My dentist has always complained about my small mouth and how difficult it is to work on my teeth. I think this is the only time someone has said this.
Just a few more concerns and please keep in mind that this may not be contributing to your situation. If you are diagnosed with OSA and you are not compliant, this could be a factor when they decide whether disability is warranted. When I first went on the APAP, after three months, I had to take my machine to the doctor to read the data that the machine records to determine not only compliance but also if the number of apneas decrease. This was for insurance purposes and whether they would cover the costs. Usually you don't have to have it read again.
Untreated OSA can lead to central sleep apnea where your brain doesn't always tell you to wake up and breath even if your airway is not blocked. If you are taking any medications that depress the central nervous system, it's a dangerous situation. OSA also contributes to heart problems, diabetes and in my case a low ferritin level which had to be treated with an IV infusion of iron. If I understand correctly and I don't know how accurate I am about the physiological reasons behind this, but less oxygen can cause anemia. Low ferritin is a form of anemia but not specific to OSA.
As I said even with this treatment, I still qualify for disability. Do you know how many times you stopped breathing? The machines they have today are small, quiet. The type of mask I wear is called nasal pillows, which fit over my nostrils with a strap.
Here is a great resource which from the American Sleep Association's Forum. I haven't posted a lot but the times I have the information has been very helpful, especially when I started with the APAP/ Also it's important that you get a sleep study in a lab as well with a doctor who is certified through the ?????. Can't think of the name but will come back later and edit.
http://www.apneasupport.org
Take care.
ETA, where do you live in Illinois? I live in east central Illinois. PM me if you want.