This is my own case story. I amazingly found relief to my pain, but have fewer medical problems than many of the people on this site:
I am 44 years of age, have always had excruciating periods since the age of 12 years (more painful than labor contractions), and have been through 2 c-sections. Other than that, I am healthy.
I developed debilitating pelvic pain at the end of last year, for 2 months, which I originally thought might be a kidney stone passing.
Multiple tests and examinations later...not a stone and nothing else detected.
My ObGyn doc thought that I might have internal shingles, and prescribed me some acyclovir - but I was unable to take it for more than a couple of days because it was so sedating that I could not even drive to work.
I am a psychiatrist, and took matters into my own hands, and did the following:
1. I completely cut out coffee and wine.
The pain almost completely subsided as soon as I cut down on these, i.e. the next day. Especially had to stop drinking Starbucks.
(Sadly, I love Starbucks coffee but had 2 cups this morning and back to being in pain today.)
2. I shoved boric acid capsules up my vagina every day for 2 weeks, to kill any lingering yeast not responsive to the usual antifungals.
You can buy great boric acid capsules on etsy.com that have tea tree oil and coconut oil in them, which do wonders to also dull the pain.
3. I have to treat my vagina like a delicate flower.
I had to get honest about this. Boyfriend cannot bang away in there for hours anymore.
Disclaimer: I do not have a hernia, nor a prolapse, nor have I had a hysterectomy - which can all cause other problems. This scenario works for me, it may not work for others.
As a psychiatrist, I prescribe amitriptyline for patients at times - most patients seem to need higher doses than your family medical doc is comfortable prescribing. Gabapentin works only for some people, not everyone. You can also try cymbalta, trileptal, tegretol. I am not on any of these myself: for me, avoiding coffee and wine, using boric acid capsules, and no rough sex do the job.