I am sorry your in pain but I sure know how you feel. I had a THR last summer and it was wonderful to have no pain after not even from the surgery. Gosh why did I wait so long. I need to have my other hip done also now but not in near as much pain as the other one.
I had pain in my butt like your talking about, I had pain in my knees I was afraid my knees were going but it was due to the hip. Your so out of wack walking and limping you just srcrew up your whole body.
Everything was good after the surgery for me..So try not to worry about it all. The pain is rotten no doubt about it and it only gets worse. So if you can move it up then do it and don't worry about everything else..
I think your insurance will take care of the chair for you in the bathroom. You need to call them and find out. I still have mine up cause of my other hip . It helps a lot.
Make sure you have a good Doc....If you smoke quit now, try and exercise your legs to build them up for surgery. Nothing terrible just move them to get the blood moving. You will fine...