One of the things about bone growth is that it is enhanced by appropriate exercise. By that I don't mean you try to deadlift 400 lbs at 3 months, but walking, core exercises, bicycling, continuing your PT exercises, etc.
Bone grows better under pressure. It is one reason weight lifting is advised as people grow older to ameliorate osteoporosis. The trick is to put enough pressure on the bone to promote growth, without putting so much that the bone begins to deteriorate. I believe that's the one of the reasons the surgeons have us up and walking right away - the healing and growth, both bone and muscle.
One thing that I did after my second surgery, to get squared away and make sure I profited from my PT, was to hire a personal trainer once I finished outpatient PT. I asked her to take my gym workouts from before the OA, and merge my PT exercises into a comprehensive workout schedule. Then we spent a month doing it, so now I have a new routine when I go to the gym.
It focused me I believe, and also I felt like I was doing my bit to strengthen the hips. There are other things that I've added to my overall fitness plan - the foam roller for kneading and torturing
muscles, a slide board for simulated skating, juggling and balancing for moving and strengthening the smaller muscles, etc. Those have helped me, but at two years, I still believe I'm a work in progress.
The bigger exercises, running, swimming, tennis, golf, martial arts, horse back and motorcycle riding that some of our great hippies have returned to can be reintroduced in time, but the basis for them is a good regimen of moderate strengthening as you heal.
At five months, it may be a good thing to get another round of PT to see if you can get over that hump. I'd talk to the surgeon and see what he thinks about it.