I'm sorry you're dealing with this! You really don't want to have surgery if it isn't necessary so waiting to see if it resolves is a good idea. If you do end up needing surgery, be sure your surgeon is going to remove just the cyst and leave your ovary or as much of it as possible.
Removal of one ovary can cause infertility and can even cause impaired function or a complete shut down of the other ovary. We need our ovaries our whole lives for the health promoting hormones they produce. After menopause, they merely change from their reproductive role to their endocrine / health promoting role.
I was in the same boat as you... sort of. For years I had a complex Ovarian cyst on my right ovary that would not go away. I would go get the US, my gyno would get the results and then tell me to wait AGAIN and see if it goes away on it's own. To come back after 2 cycles.
She constantly blamed my thick lining on my ovulation. Blamed my pain on just bad periods and told me there was not much she could do. I was spotting, I only had about 15 days between each cycle and the pain I was in a week or 2 before my period was excruciating. My periods were 10-15 days long UGH (she thought this was normal?)
So after my last US where I was diagnosed with a Endometrioma Cyst on my right ovary I called a specialist. Every other time my cyst was called a "hemmorhagic" and this time it was different and my gyno never called me to follow up or discuss this so I went a different route.
My new gyno informed me this - Endometrioma cyst usually come from Endometriosis. So it's more than likely NOT going to go away on it's own.
I had a LAP done. Was diagnosed with numerous cyst on both ovaries ( she removed), severe endometriosis and scarring from years of having it and not going to the doctor. The doctor informed me she could not imagine the amount of pain I was in because it was so severe.
I now have to go back in a few weeks to discuss my options of ovary removal, hormone therapy or something else because she was not able to get all the endo out.
I'm only 28. If you feel pain and it is not subsiding. Get a different opinion. Because I waited so long and never was taken seriously my Endo got so bad that she couldn't get to most of it or was unable to remove. Get it before it gets worse. Endo is for life but if it's managed well you can live a normal life too!
Hope this helps. :)