pelvic pain? Or vaginal pain?

The vaginal pain called vulvodynia is sometimes relieved by eating a low oxalate diet.

The other internal pain is often treated the same way as fibromyalgia, and is considered by doctors to be similar.

Hence the Neurontin and antidepressant.
A visit to the fibro board here may be helpful.

What type of cyst did you have? Was it a pilonidal one?
Those are very painful, sometimes even after removal.