Unfortunately us women with PCOS have to work twice as hard to lose half as much as the normal person. Our enemy's are white flour, refined sugar, and white rice. Pretty much any food made primarily of a carb that has been processed in such a way as to strip out ingredients that hinder quick and easy cooking.
I started the fat smash a few weeks ago and have lost 8 lbs (due to this holiday I've just been trying to not gain- not really working on losing.). It basically teaches you to cut out the bad stuff and eat more of the good stuff, fruits and veggies, brown rice, beans, whole wheat/whole grains, etc.
Because you have PCOS you'll have to eat this way the rest of your life, no "diet" will work for life.
I've had it for years and ballooned from 170 to 221- so I feel your pain! This is the only thing that has worked for me- I can't do Atkins because I have kidney problems- I tried and trust me I regretted it- I became so violently ill I almost landed myself in the hospital because I was vommiting my brains out!
Check out the fat smash- the first few days are tough- but if you can make those you can definitely do this- I think it's a great diet for people who have PCOS.
There are also some great PCOS diet books- search for them on amazon
"The PCOS Diet" is the one I have and it's diet is basically what the fat smash is telling me to do- but the fat smash goes through phases and is more specific.
Good luck!