Suggest Treatment For Irregular Menstrual Cycle And Weight Gain

Hi Doctor. I am 28 yrs old and I have PCOD which was diagonised in my teens. My menses started when I was 8 and stopped when I was 12. Since that time I have been getting obese. I have tried one too many diet regimes since I was ten, helped by my mother. I have done a few exercises, but my asthma restricts me from doing more. I have been on Metformin since 12, but my menses are zero. I saw a specialist recently and he gave me a seven day medicine course which brought very heavy flow for 6 days. After that its zero again. He suggests that I do a surgery to burst the cysts, which I am not so fascinated about. But now I am putting on more and more weight, which is depressing me. Is there anything else that I can try out. Thank you.