I have a friend who's had Parkinson's for about 7 years. Some days she shakes very little, others very much. Some days she can walk, but even on those days, she may just suddenly "freeze" and it can be very difficult to get her moving again. Quite often it's also difficult to understand what she says. However she is very active, extremely cheerful most of the time, and loves to participate in pub quizzes and the like. She also swims quite often.
For some reason, the medics are always experimenting with her medication, and this can have a very detrimental effect.