Mick, I had TKR 10 months ago. The first few weeks are extremely hard. Lots of pain and difficulty sleeping at night. By week 4 post op, the pain started to lessen and I was able to sleep better. To guard against the constipation that pain meds can cause, I was faithful to take Miralax twice a day and drunk tons of water. It worked. The PT is hard because it hurts. No question. But it is the most helpful thing you can do. Also be patient with yourself. Healing takes a lot of time.