Physical therapists’ end goal is for you to get to the point where you can maintain on your own. In order to do that, they will push you beyond your comfort zone a little bit. Physical therapists will encourage you to go beyond what you think you can do to help you get back to being independent.
Most people only go to therapy a few times each week. Stretching and strengthening exercises need to be done almost daily to get the improvement you need. And yes, physical therapists can tell if someone is doing their home exercises or not.