So had this one line from a song stuck in my head and i cant for the life of me remember the rest of it, and have failed to find it via google. Its about a guy beong cheated on by his girlfriend and the only line i really remember is "but ive seen you" or "but i saw you" its the main line of the chorus and i thought the title. Not much to go on i know but any help is appreciated, its drving me mad not being able to remember it =P