Suggest Treatment For Severe Pain In Hip Bone

I'm a 65-year old PGA teaching professional and I have pain in what I think is the iliofemoral ligament of my left hip. The pain runs from just left of the hip bone down the top of the thigh toward the inner thigh. It is especially bad if I hit golf balls (I'm a right handed player). to give you an idea of the hardest thing to do, when I get into my truck on the driver's side I have to help lift my leg with my hands and arms. It is getting worse and now hurts even while I sit. Any suggestions?