M.L.
Sounds more like the main issue is not the milk or the bottle but the comfort item that he uses when he falls back in the tired mode. One of the big things I have found is to just casually "forget it" when you go through a routine. If you don't think it is a big deal, then they won't either, or offer a different form of the same thing (IE in a sippy instead of a bottle, or real milk in a bottle instead of formula.) Try also giving him an empty bottle to play with througho out the day so that the bottle itself no longer becomes a special privledge. Otherwise, get rid of them, (While he is watching!) so that later he will believe you that they really are all gone and that it is not a mom vs kid power struggle.