It's hard to say what it is. It sounds like he might be grooming you for one day when he is interested, but that day hasn't arrived yet. Is it fair and how long can you wait? I guess are separate questions. If you don't mind keeping things as they are then probably just keep going like this, though nothing is certain and you may lose him as time goes by. If you want certainty I would probably just ask him if he is interested in you or not (seeing how close you are, this question shouldn't be a problem). I suspect that if he's grooming you then this will be a threatening question for him. If he answers that he's interested then the pressure is on him to act, if he answers that he's not interested then he loses control over you as you will move on and look else where. Unless you are happy with the way things are, I would advise you to challenge this ambiguity.
Don't cry, don't regret and don't blame
Weak find the whip, willing find freedom
Towards the sun, carry your name
In warm hands you are given
Ask the wind for the way
Uncertainty's gone, your path will unravel
Accept all as it is and do not blame
God or the Devil
~Born to Live - Mavrik~