if the pain is in your groin and radiates down to the knee it's probably arthritis. if it's in the side it could be trochanteric bursitis or IT band inflammation, or maybe piriformes syndrome. if it's in the rear and radiates down the back of the leg, it could be sciatic pain or pain from a pinched nerve in the back.
have you had xrays? or seen anyone for it? you could try NSAIDs and PT to see if that helps. if it's arthritis you may be limited to NSAIDs, injections, or maybe even surgery,depending on how bad it is.
I would see your doctor and ask to be xrayed.
It sounds like it could be muscular. Maybe your IT band? Have you tried doing stretches?
Reviews I have read on glucsamine and joint juice are mixed. Some swear by it.