You did the right thing. Here are a few methods that I have implemented into my bowhunting adventures.
To begin with, that is why I always buy a bear tag. I likely would never shoot a bear otherwise, but, in the event that I would feel I’d have to shoot one, I want to be able to do it without having to explain why I didn't have a tag and/or, why I felt threatened enough to justify killing it in the first place. (Although in the case of a Grizzly, I suppose the tag scenario wouldn't be an option anyway).
In addition to that, on my back, I carry a 12-Gauge short defender-style shotgun loaded with slugs. The scabbard that it sits in, straps on like a back-pack, and in no way hinders maneuverability with the bow or in the bush. The pistol-grip of the shotgun sits tight right behind my shoulder, and I can reach back and be armed in an instant.
In addition to that (if that fails), I always carry bear spray on my belt.
In addition to that (if that fails), I have a 16" Bowie knife sheathed on the front strap of the scabbard at my chest (for close combat).
In addition to that, (if that too fails), I have a good life-insurance policy so that my family is taken care of.
In addition to that, I am prepared to meet my maker. If I should die at the jaws of bear, I believe that God would agree that at least I had done all I could to stay alive, and that I didn’t go down without a fight!