There is not nearly enough information to draw that conclusion. We have no idea what transpired in that house other than two women are dead and a killer/killers are on the loose. Who it is say they had no way of defending themselves...sometimes even the best prepared fall to their adversary. As good as you are (or think you are) there is always someone better than you.
I'm speaking in generalities because we don't know the specifics. Once a home invader enters the house, the options for the residents are limited. That anti-gun lady wants to remove one of those options, protect yourself with a gun.