Well Karma, it sounds like he is being truthful with you by telling you he just wants to be friends. Meaning- that he doesn't feel like he wants to be your "boyfriend".
So in effect by saying you want him back, you are saying-" It's ok...walk all over me...I love you even if you don't love me back.
You are opening the door to being the biggest doormat of all time, now and in future relationships. He's not the only fish in the sea. Its a big world out there.
Go catch another fish that likes what you have to offer. And can give you what you want and deserve in a relationship.