Well, I'll give you advice, but this is assuming one thing and one thing only: he's not afraid of contact.

My advice here is continue on like usual, but... when you get a moment alone and that impulse to love him grows strong, I'd give him a hug and ask him, "Could we stay like this... just for a moment?". The reason you should do this is to determine a few things:
1) Is he afraid of you? I know you've dated, but... he's not sticking with you anymore. Maybe something's bothering him? If he refuses to stay put, hold him a little tighter, but if he honestly resists, let him go, and walk away. Don't talk to him. Just. Walk. Away. I think he might need some downtime, especially if he refuses you. It might hurt him, keep this in mind, but he needs to think about this. If he's not commiting, you shouldn't be tearing your heart over thinking about him; it will only hurt more.

2) If he accepts, then you know you still have a chance. Ask him something that's been on your mind lately. One such example is, "why did it all change?". If he doesn't know what you're talking about, I'm not certain he has given enough thought to this relationship as you have... However, if he does ask what do you mean, simply reply, "what do you think it means?". The idea here is to instigate from him a response. You got to know him better.

3)???

4)Profit!

Sorry, 3 & 4 was just for kicks. Anyway, I hope you read this and take it to heart. Ask me any questions if you have them. I'll be glad to respond.