Oh, the joys... Not sure what to tell you, except to sleep with lots of pillows and move them around until you feel more comfortable. I sleep with a body pillow - between my legs when I'm on my left side, and at my back when I'm on my right. Plus, I have two pillows under my head, one fat one under my top arm, and another one that moves around all night with me as I need it for support. My sleep isn't the deepest anymore, but I look at it as preparation for when the baby is here and I'll be waking up every couple of hours then.
But I do feel your pain - it stinks to wake up in the night for no good reason other than discomfort. Now I find that I can't really even roll over very easily from one side to the other without getting shooting pains in my lower pelvis. (And I *have* to change sides several times a night, or I start getting the hip pain that you get.) I literally have to use my arms to lift my leg over, as my ligaments must be so loose that I can't move the leg on it's own - and it still hurts!