I was given the suggestion to try Kym Campbell's 30 day PCOS challenge. On May 22nd she is starting the next challenge. Both my Mom and I are going to try it. Also maybe if your boyfriend learns more about PCOS he will be more supportive. If you click on this link it will bring you to the book I've been reading. https://www.amazon.com/PCOS-Workbook-Complete-P...(Phone number can only be seen by the question and answer creators)&sr=8-3
I like it because it explains all the all aspects of PCOS really well, especially the weight gain. Maybe if you can get him to read those few pages it will help him understand better what you are going through. I feel it is really important for your loved ones to be as educated on your condition as you are so that they can support you better. I hope this helps. :)

Pressure from loved ones to lose weight is not normal. They should be supportive no matter what your weight is. He might be encouraging you to lose weight as it is a risk factor for other things, however, there is a fine line between encouragement and pressure. And to add to this, weight is not a true reflection on health — people can be slim and have health issues. I would bring this up with him as it's not helpful to bring you down like that. A combination of underactive thyroid and PCOS will make it harder for you to lose weight. With PCOS you may have insulin resistance, and high insulin levels are at the root of weight gain/stall. A low carb diet may be beneficial for helping you lower insulin levels and thus reaching your ideal weight.