Husband's Low Sex Drive

Within the past year, he has been showing less and less interest in having sex, usually lucky if I can convince him to do it once a month now. He says that it is due to stress from his job, but being a teacher, he gets at least a full month in the summer off, and even then was showing little interest. I know he is not cheating because we share schedules and we both have tracking apps for safety mainly but also for accountability.

I know I shouldn't take it personally, but I also have put on 10 pounds over the past few years and really haven't felt like I look my best anymore which I am working to get back in shape. But his rejection of my advances in the bedroom is a huge hit to my self esteem. Also, we haven't even tried for children yet and I am afraid with his low sex drive and my PCOS, it will make things even more difficult.

Anyone else have trouble getting their man interested?? What can I do to help get him in the mood?? Should I have him see a doctor or go to couples therapy?? I'm at a loss and not only sexually, but also emotionally frustrated now.