I have had it for years. I stopped taking my med for it when I got pregnant because it's actually better now than it has ever been, but when I get really tired, it kicks in. What I've found that helps me best:
1. Even though not always posible, get in bed and try to get to sleep before you're exhausted. Exhaustion always makes it HORRIBLE for me.
2. This may not help you, but is my God-send - weight. Have your SO put their legs over where it's bothering you (for me, the worst is usually in my hips). Or get a heavy or weighted blanket and put if over your legs. This stinks if you are already hot all the time like I am, but I'd rather sweat than feel that sensation. If you can fold it to only cover the areas that bother you the most, it might not be that bad. For me, it's my hips and knees.
3. Exercise. I can't do it as often or as much as I used to, but try taking a daily walk or doing some wall squats (if you're legs are up to it - if not, I wouldn't attempt it!). Sometimes just stretching the joints or moving them around a bit helps, but not always.