I personally love black bear meat but to each his own. One thing to remember is bears have alot of fat that accounts for alot of their weight. If the bear was under 120lbs ,than 18lbs sounds about right because alot of it is unusable because of all the fat. Bears also carry trichinosis and you should really only eat the back straps and the lean portion s of the hind quarters.
As far as your so called friend is concerned, I dont see how its any of his biz, how much meat you got, or what you shoot in the 1st place.