Diagnosed with PCOS. Pcos. please guide.

I've never had regular periods since i was 16. Last yr I got married but after a month or two i didn't have periods & was subsequently diagnosed with PCOS. In tests my FSH was high & other hormonal imbalance. I consulted two different gynes and i'm confused. The first doc prescribed a hell lot of meds and asked me to completely stop any kind of sugar intake in any form, not even fruits. And that the course will be long for 1-2yrs. While the other doc asked me not to have too much of sugar intake but limited. And prescribed me Meprate and only an iron pill. (Seeing my other prescription she asked me to have only the calcium pills from it. Also, for other meds she said that she can't believe why that doc had prescribed the suchs medicines!) Anyways, the thing is I went with the second doc now my periods are med influenced & i still don't get normal periods. Also i've NOW started gaining weight & i dont know if it's cos of my deskjob or PCOS. Please Guide.