How hard is it for you to get another GP? Can your dietician recommend a good one? Usually the best way to get a good doctor is to ask around and find out who other people use and who they like.
I think they could treat your PCOS with hormones, if they wanted to, but they've got to send you to a freaking gynocologist. That's what gynocologists went to medical school to learn: how women's bodies work, don't work, and how to make them work. It's not for a GP to be fooling with your hormones or treating (or dismissing) your female problems.
The only other option besides hormones is the removal of your ovaries, which will mean you have to be on supplemental hormones until middle age, but it's like my gall bladder, isn't it? I have to take medicine to make up for the function that I lost when I lost my gall bladder, but what's not there can't cause you pain. If your ovaries are the sole source of your pain, then they can't hurt you if they're not there. Being a person who doesn't want kids, I'd say take them puppies out. But even if you do want kids, the liklihood you can conceive naturally is fairly low anyways, since your ovaries are producing cysts instead of releasing eggs. It can happen, but it's hard. Like I said before, I have a friend who has it pretty bad and she's never been able to have kids. I've also seen her when she's had a cyst rupture and she was so sick-looking and was in terrible pain. Another friend had a cyst rupture while she was out shopping and her mother had to borrow a wheelchair to take her out to the car because she couldn't walk for the pain. They put her on birth control pills and she hasn't had any more problems since. I think, though, she had a second one to rupture before she got the pills.
So know that you are not alone in your pain on this matter, and that it's not in your head and you're not being a hypochondriac. Maybe you need to report your doctor to the medical malpractice board in your country, because her lack of treatment of you seems criminal. When even a dietician says you're getting bad medical advice/care, then you know something's wrong.