15 months post-stroke (Ischemic)

Anyone else feel like you're not making enough physical progress after a year or more post-stroke? How do you deal with it, the fatigue and the frustration?
Still in wheelchair most of day, only can walk with walker for a few minutes at a time before legs (and arms) get tired. Need assistance with quad cane. I'm 83; too old? Was getting around fine before stroke, although left knee hurt with arthritis. Now both knees hurt, everything's a struggle, can't do steps or stairs, and have lots of tension in whole body. Not sleeping well; wake up feeling exhausted, drained. Physical therapy once a week doesn't seem to be helping much. Do I need more, or different kind? I feel like I should be more mobile and independent; still need caregivers' help.