Nancy, I hope you are feeling more confident in your recovery as you seem willing to ease up on your leg. I'm sure you've heard plenty about the gentle approach on here, and that applies also to legs that are reluctant to bend.
Regarding the drugs -- are you careful to take your ibu and pain drug with a full glass of water and some food? That helps soften the GI effects. As you push your leg less, you can probably drop down to one half percocet and then as you have less pain, space those out. You won't even notice withdrawal if you wean slowly like that.
Your knee needs extra TLC because it's had multiple surgeries. Very often the response to knee issues is the body shuts down the innervation to the quad and it becomes weak because the body is staying, "Spare the knee!" It's called "arthrogenic muscle inhibition." It took me two years to get my quad back. It's not time yet to make your quad a priority. Just as we get kids out of diapers before worrying about applying to college, this is healing time for your knee while establishing normal function and a decent bend. Down the road you work on better flexibility and strength, but certainly it should not be pushed until maybe the six month mark. De verdad!