My mother had her hip replaced about 2 years ago. It is doing really well. The doctor originally told her that it was bursitis and she needed physical therapy. The therapist was totally convinced that she was not getting results because she wasn't doing her exercises. The reality was that her hip was bone on bone so nothing was going to help, and the therapy actually made it far worse very rapidly. When she finally insisted on seeing the doctor again, turns out that the exercises the therapist prescribed were exactly what not to do with a hip that was bone on bone. The recovery wasn't easy, but she got through it.
It really helped her to have my dad in charge of her medications. He is really precise and meticulous, so if she was to get a medication at a certain time, she got it exactly then. Not 5 min later when she was done with her book or whatever. Also she was really loopy on the pain medications, and none of us thought that she should be in charge of the medications.
Our biggest struggle was getting her to eat. There were times when Jess and I cooked at her house, rather than bringing food to her. Smelling it cooking really helped stimulate her appetite, so if she hadn't eaten more than a small cup of applesauce and maybe a half cup of soup over 2 days, we went and cooked at her house. It wasn't for lack of food, of course. It was just that she wasn't hungry, or she wasn't aware enough to register feeling hungry.
At some point she will have to have her other hip done. It is in much better shape because the exercises were all targeted at the other hip.
If you have any specific questions, I will happily ask her and give you the answers.