TTC -long

I'm new to this and i was hoping to explain my story and get some help on what to do next. I'm at a standstill.

I've been experiencing the worst pain on my right side for over 3 years( where the fallopian/ovary is.) thought it was endometriosis. Laparoscopy showed nothing of endo. Did however show i was born with only one fallopian tube and ovary(on my left) i have been diagnosed with PCOS but nothing has settled my pain. Is unbearable. 100% worse a week away from my period. Dye test showed no blockage. Drs thought it was a gastro issue but colonoscopy showed nothing. Was placed on letrozole with no end results except horrible migraines. I also am scared i might have ovarian cancer :( symptoms are too close.

Can anyone give me some advice on a next step. No pain decrease, no pregnancy... just nothing. Ready to give up