Well, you stated the boundary, and he abided by it.
I think what we always secretly hope is that they will not simply honor the boundary, but change their behavior to something we REALLY want (i.e., that they quit drinking).
If he keeps abiding by your boundary by not drinking around you, then you have to decide whether you are willing to accept a relationship with someone who would rather go off and drink on his own than be sober with you.