Butterfly, I hope this helps a bit. I always panic when I gain any weight but I expected to over Christmas holidays. It looked as though I had gained almost 10lbs but after a week of doing nothing different but going back to normal, I was down 9 of those 10lbs. I'm actually only .6lbs more than I was and things are still shrinking. Our bodies are weird and can hold a lot of water just from stress...heck, sometimes a good poop can clear up why the scales were so messed up (but don't poop on the scales or they'll be REALLY messed up).
As much as it sucks, and PCOS and ANY chronic illness does SUCK, please remember that every single time you don't give into a craving, you take that energy and use it to exercise, you eat a healthy meal instead of junk, or make any healthy decision, your body appreciates it and you are getting healthier. It doesn't feel like it now - it may not feel like it for ages...but you, my dear, are amazing! You are persevering, you are preventing your weight from taking over, you are taking control of your future and trying your darndest to do the best you can.
While that may not show outwardly right now, you're a trooper and pretty darn incredible.