What is that song?

I've been trying to rack my brains on who sings this and what it's called. They kept playing it on the radio and would never tell me who it is, but I knew it sounded familiar. So one day while they were playing this song once again, I ran to the computer got on the radio station's website and found out what they were playing. It took a huge weight off my shoulders and if you are a music addict like me you know what I'm talking about. Then of course the very next day I was listening to the radio, that song came on. Apparently the radio station has it out for me or just like to tease me because after the song was over they said the artist's name and what it was called.