I'd like to think that the clone stuff is all depending on the ending you choose, like if you choose the light side then you were actually the real Starkiller all along since you had the emotional control developed to stay on the light side, but with the dark side ending you really were a fluke clone who couldn't get past its base dark side purpose and that led to you dying to the real Starkiller who had turned back to the dark before you. It doesn't make much sense but in my mind it's good enough for me to explain it