Ray -- I feel your, well her pain. I had my right knee replaced in September. It hurt -- but that's what the pain meds are for. The doc, nurses and PT really stressed taking the meds BEFORE the pain revs up. I am glad I listened, I would have tended to tough it out, be a man and suck it up. Instead I was taking those happy little pills every 3-4 hours. And I can honestly say the pain was not that bad.
On that note -- take the meds about 30-45 minutes before PT -- it helps, cuz that tends to hurt if you do it right.
Like others have said -- she needs to do the exercises. The first two weeks are the most critical to keep scar tissue from forming and to regain flex. That's her job for a bit. I had my surgery at 10:30 on a Wednesday. They had me out of the bed and in a chair by 3:0 that afternoon, and in PT Thursday morning. I was home Friday evening. Took 3 weeks and a day off from work.
It was such a success I am not hesitating to have the other done. I get my left knee replaced March 3rd.
It will make a big difference for her. Just gotta get through this rough phase.
Good luck to her and you. I'll be thinking of you two.