This is normal! I did it for about 6 or 7 months both times I was pregnant. It is the relaxin hormone getting those ligaments looser so that the baby will be able to come out. Don't be surprised if you start popping down there as well. I have hypermobile joints so I tend to do it very easily. My youngest is 28 months and I am finally almost tight in that area. Perhaps ask your hubby to rub the inner thighs and your pelvic mound. Mine used to do that for me and it provided a lot of relief.
I do want to warn you that if it hurts more when you walk, then you might go numb randomly, kind of like the sciatica makes you leg go numb. Just have a cart to hold onto or if you can ride one of the electric carts when you go to the store. I know it looks funny because you aren't "handicapped" but for this pregnancy you are getting there.
Good luck and I feel for you. It will get better after you deliver I promise!