In a way, I sympathize for OP but the truth is, we ALL (if not most of us) have had someone come and go in our lives. Most of us are not even a quarter of way through our lives yet we feel like there is nothing left. That is BS. You may not take this the right way because there isnt one but believe me when i tell you that you'll get over it. It may not be tomorrow or next week but you will eventually see that that person was not the right person for you. There is always going to be someone better out there you just have to be patient. For now, You should try doing something to get this off your mind. Try going outside/hanging with friends.