Re: "hidden endometeosis"???
The only problem with considering a hyst is that your uterus may have nothing to do with the pain and it will not only be for nothing but the surgery may cause new problems.
I was on birth control from the age of 20 until 40 years of age (I also don't want children) and when I hit 40, I started experiencing pelvic pain and heavy irregular bleeding in the middle of my "cycle" (if you can call it that on the pill). My doctor told me that the pill was probably causing the problem and he wanted to put me on a different pill. I say no way and went off the pill completely. The bleeding immediately stopped and my cycles became regular almost immediately after stopping the pill. However, I experienced, what I now know to be ovulation pain. It was quite excruciating and left all of the muscles and organs in that area quite sensitive. Since I did not know what this was, I went back to the doctor and he did an ultrasound. They found an 8 cm ovarian cyst which I watched for a year and a half but which I eventually had to have removed, along with my ovary and tube (last April). Throughout this entire time, I would have ovulation pain which would put me out of commission for at least a day. In addition, I had pain from the cyst occasionally as well (it felt like someone had kicked me in the gut .. only way to explain it).
Heating pads worked at reducing the pain as did the anti inflammatories such as Naproxen and over the counter ibuprofens like Advil (these are better than pain killers at reducing gyne pain as they counter the prostaglandins that are responsible .. it's not power that you need with this kind of pain but the right mechanism for attacking the cause). They did not work completely but they reduced the pain enough for me to function.
After my surgery last April, I acquired a new pain and that is pain with urination. Evidently the catheter they insert during surgery can sometimes cause a type of urethritis that is ongoing. I was given potassium citrate to take regularly and told that it would go away in 6 months .. that was about 8 months ago. The pain is much less (I was starting to get it even when I did not have to urinate) and is indeed going away but tends to be related to my menstrual cycle.
All this to say that there are many possibilities that could be causing your pain and starting to remove organs blindly, hoping to alleviate the problem, may not be the right approach as this can actually make things worse.
Have you considered going to see a pelvic pain specialist ? Try to find one in your area. You can always start by seeing a pain specialist and then try to get a referral to a pelvic pain specialist from that person. Pain specialists are usually anaesthesiologists with special training in pain. Some of them go on to sur specialize in pelvic pain. Usually a pelvic pain specialist works with a team of specialists that include a uro-gynecologist, physiotheraphists who specialize in pelvic pain, perhaps a gastroenterologist etc.. They will do a work up on you to get to the root of your problem and they will choose the least invasive method to get rid of your pain. These specialists have found that many women end up having unnecessary surgery which sometimes makes things worse (ie. causes new problems).
If you think that a hyst is the only way, this is your choice, of course. I just wanted to let you know that there are other options for pelvic pain that cannot be explained by the standard tests. It is evidently more common than we think. You may be interested in picking up a book called,"A Headache in the Pelvis: A new understanding and treatment for chronic pelvic pain syndromes" by David Wise, Ph.D. and Rodney Anderson, M.D.
I hope you find a solution to your pain very soon.
All the best.