Pcos beginning diet advice!

I have PCOS and have been TTC for almost 2 years. I have a almost 6 year old son who's my miracle baby (wasn't even trying and found out on April Fools day i was preggers then 6 days later found out I was 6 months along lol crazy story could share sometime if anyone wants). Well I need to find a diet that will actually get me to shed some pounds and help. I have heard people talk about Keto but am scared to try since some people consider it a "fad diet". I really just want this to work my bf wants a baby and my son wants a baby sister he says. I feel like a failure... I am actually back on birth control to regulate my cycle. My weight has fluctuated so much since I came off of it when we decided to try for baby so dr says the weight has to go and I've never been successful since I was diagnosed. I mean I've always been bigger built but never this big..i feel so down and disgusted...I need help and meal plans are the best for me cause I suck and thinking and planning with diets. Any help is greatly appreciated.