A man who downright doesn't WANT to "get attached" to you is probably a worse prospect for dating than a man who is currently on fire.
You know what you got into. You know his side of things, you know what he wants and doesn't want and you KNOW he doesn't fit what you want. As far as he's concerned, you're a girl who will settle for less than she wants/deserves and that's exactly what a man wants when all he cares about is sex. You're a toy to him whether or not you want to believe it.
This should really be a no-brainer. You already know the only RIGHT answer for you, don't you?
Welcome to the board. You have already gotten some good advice. IMO he doesn't want a relationship with you. He will continue to sleep without and enjoy your company without the committment for as long as you allow it. Sometimes we don't listen to what is being said, but in this case he is being very clear to you. If you want a relationship or committment he is not your guy.
I know it must be hard considering that you care for him and he has been in your life for the past year, but think about it, he will not give you what you want, and by him telling you and you going along with it, you have told him by your actions that you are okay with it.
His stance is not going to change. The only person that can make that change is you. Are you willing to let go?