@Annie LTKR What that PT told your husband is totally false! That's one of the many reasons I refused all formal PT after my revision. Most of them want to push our knees far beyond what they're ready for in order to get "good" numbers early on; maybe to justify their existence. My husband says none of them really knows what they're doing anyway. In his case, he went to a few different ones when he had a problem with his arm and all of them gave him totally conflicting exercises and advice, none of which helped at all, and all of which made things worse. He also watched what they said and did with me after my original TKR; it was obvious to him that they were doing everything wrong in the case of my new knee.
Anyway, you will have very low ROM for a while as your knee has just been chopped, sliced, diced and hammered on and it needs time to recover from that assault. Think about how long it takes to recover from a simple broken bone, and realize this is much worse than that. Your knee is swollen and injured and your ROM will reflect that for quite some time. When the swelling, inside and out, finally goes down, your knee will bend nicely as the implant is perfectly able to bend; it's your tissues and the rest of that area that need to heal. Before your surgeon put the implant in your knee, he checked to make sure it worked, so it's there just waiting to do it's job when the rest of the area heals.
If you decide to continue formal PT, make sure you let your therapist know that when it comes to your body and your knee, you're the boss and what you decide is what will happen. You can listen to advice, but the final decision is yours and yours alone. Just as you made the decision to go with a TKR after listening to your surgeon's advice, you make the decision to continue or cancel PT, you make the decision as to how you want to recover and how much PT you will or will not do. If the PT listens to you and follows your limits without questioning, arguing or threatening, then you will be fine. If your PT does any of the above, you need to find a different one asap!