@AprilM
I'm sorry you're having a slow recovery, but you do seem to still be making progress, even though it's slower that most people's.
I'm quite sure in my own mind that all the aggressive treatment your knee received in the early days, from those "no pain, no gain" therapists, set up an inflammation that has slowed down your recovery.
Time is on your side, though, because it takes at least a year to achieve full recovery and your ROM (Range of Motion) can continue to improve for all that time, or even longer.
If you think of this recovery as a race, it's more like a marathon than a sprint, so endurance and patience are important. I know this is a great trial of patience for you, but I think you're going to get there in the end.
Keep doing what you can, taking that walk to the end of your driveway and back, resting, icing and elevating, so that you give your knee the best possible chance to recover.
Hugs to you

and my admiration for your perseverance.