There are so many things I have learned because I have PD. I can tell you these things and hopefully inspire you to also look and see what experiencing the pain of this disease has done for you. If you aren't finding anything, then I would say that the pain and anguish this disease has put you through has all been wasted.
There are two kinds of pain: 1) - pointless pain and 2) purposeful pain. Pointless pain gains you nothing and makes you bitter. Purposeful pain grows you up and teaches you about people.
So, either way you can have pain but will it be pointless or purposeful?