Hi, Nat! I have had RLS, now to be officially called Ekbom's disease, for as long as I can remember. It's genetic in my family. NO, it's not caused by diabetes. No one really knows what causes it. But some people get it during pregnancy, and some people get it as they age, and some people get it because of neuropathy or renal failure. There is no perfect treatment for it, although there are a lot of drugs you can try. They all have side effects, and many of them are habit-forming (read: addictive). But they are better than jumping out of your skin all night!
There is an organization called the Restless Legs Foundation, which has information about it at
I would recommend that you read that site, and print out the relevant parts, and take them to your doc. You will need to discuss what you are willing to do about it. In my case, I take Xanax (alprazolam) to which I'm developing tolerance, and so when I have symptoms, I just get out of bed, and do something (often the computer, and wiggling the whole time I'm there!). But I have the freedom to sleep during the day when my legs aren't bothering me. If you don't have that freedom, you are in a pickle. That's when the drugs are worth considering.
Good luck from another Nat!