Actually many times it happens that an idea comes to your mind and you give lots of thought to that idea. You realize that this has potential. As a next step you plan to gather as much of data related to it. You go to internet to search for it and eureka (?) you find that it is already implemented and running.
Don’t feel sad. Now I am used to it. No need to be sorry but the important thing is to keep getting excited about ideas. You never know which idea will be liked by people. And finally you have to understand that you are implementing the idea for your satisfaction.
I have seen closely how people dedicate their time and life for an idea. How they work hard towards it? Irrespective of the fear of negative result they keep themselves passionate and excited about the idea. You really feel inspired after meeting such people. Inspiration and passion are contagious.