I am so sorry you have experienced this, and I completely understand.
I had the same experience in 2016 after another knee surgery, and it was common practice once a week to "make Lisa cry." It was the PT clinic joke for months, as the recovery from that type of surgery was long, requiring me to rebuild my hip/glute/quadriceps muscles. In between strengthening exercises for the leg, the other goal was to force the knee to bend further. I simply didn't know better back then though, and after 5 months on crutches, unable to drive, I listened to whatever nonsense they told me.
I would swell horribly for 2 days after that, and I needed valium to get through the forced bending sessions....All this did was delay the recovery, create loads of scar tissue due to chronic inflammation, and gave me "PT PTSD." .
I don't use that phrase lightly either. When I knew the knee HAD to replaced, I found a surgeon with the Bonesmart philosophy (while not even trying!!), and he said NEVER, EVER let anyone force my knee to bend or straighten. I found a PT person I knew and trusted (from an ankle injury the winter before), and asked her how she did things following a TKR. She was great overall, but this involved very open communication involving what I would/wouldn't tolerate. She also said she would do whatever my surgeon wanted and not let her own ego get in the way (meaning she wouldn't blow off his suggestions!!). She cried with me when I described what I had gone through before, and she said NO ONE in PT should ever subject a person to that!!!!
My surgeon DID have her go slower/gentler than she would have liked, but in the end, it worked. She agrees I was an interesting case that taught her a lot, and "gentler is better." I still only have 105-110 degrees of flexion (bending) depending on the day/week/activity level, but at least I didn't end up with another chronic inflammation problem. I also only had 120 before the TKR, and it's well-known that range of motion pre-surgery is a big factor in your post-op range of motion. It's not a guarantee but does play a role.
Another interesting thing to note---- during my TKR (May 2019), my surgeon had to cut out a huge amount of adhesions from that 2016 rehab experience. The knee was FULL of adhesions.
The ONLY way that could have happened was from PT-induced chronic inflammation in 2016. I had documented EVERYTHING and had the data to prove it.....1) I had had a scar-tissue removal surgery 3 months after the 2016 surgery--followed by more months of intense PT, 2) I had had an MUA 9 days later, after the scar-tissue removal surgery, because I lost 20 degrees of ROM overnight. So the smart-aleck in me asked my surgeon how was it possible to have a knee full of adhesions after they had been cut out???? He gave me the answer I had felt in my gut for 3 yrs-----the forceful bending and overaggressive PT created chronic inflammation, which has been scientifically proven to CAUSE adhesions. A lack of movement didn't cause them----too much bending and overuse caused them!!!
If only I had known ALLLLLLL the range of motion issues were NOT my fault or just dumb luck----it was from too much PT, the wrong kind of PT, and not letting the knee heal before abusing it terribly. I swore no one would ever abuse me in such a way again, and I try to preach it like crazy to anyone walking this same path. I wish you the best in your journey, and I hope you will advocate for yourself, even if your surgeon or PT makes it difficult. Sometimes the only real advocate we have is ourself.
--Lisa