Cherry,
I have PCOS, and, like you, was quite upset when I was diagnosed. The good news is that it can be well-treated and controlled with medications, and is one of the easiest infertility issues to treat (and doesn't necessarily mean that you're infertile at all - depends on whether you're ovulating).
Most books I've read state that up to one in ten women has PCOS, but many do not ever know it. It frequently goes undiagnosed because doctors are not aware of it, or don't know to look for it unless someone is obese, has a beard, and has stopped menstruating.
I've found both metformin and aldactone to be very helpful! I'm just now cutting back on the metformin, since I take around 12 medications and want to let up on my liver some. So far, so good!
Many of the symptoms of PCOS overlap with both lupus and the side effects of steroid treatment, like hair loss, and skin rashes and acne. And having PCOS makes you much more likely to have a whole slew of other issues, among them autoimmune thyroid disease, metabolic syndrome with diabetes and high cholesterol, and lichen planus.
Funtimes!
Really though - lots of women have this, and many without even knowing it. Don't freak out just yet! Have you started any medication for PCOS? Some of my friends couldn't tolerate the GI side effects of metformin, but I've been fine on it. It really was the first thing to make a big difference after I started feeling bad. Lupus, PCOS, and Hashimoto's seemed to hit me all at once, and it took a long time to untangle everything and get the proper diagnoses and medications.