>>1 Is playing the piano really what you want to do with you life?
If you answered yes then make your attitude a positive one. Just because you think you can't do something doesn't mean that you can't. You can do it if you set your mind to it and concentrate, focus, and use the criticism thrown at you to strive for success.
If you answered no then that is 100% fine. You can still enjoy music by listening to your favourite pieces. You can enjoy music in different ways, you can edit it, produce it, write it, etc.! The sky is the limit! You could also find something else that you want to do with your life, try new (safe,) things and see if you have another passion that you can strive for.
I hope that I helped~! Good luck~! :3