Either she values her life enough to be willing to kill to protect it, or she doesn't.
Short of an effective firearm and the will and skill to use it, there is nothing but vulnerability for her...
Please don't indulge her illusions of safety afforded by "non-lethal" "weapons". She should remain fearful...it might save her life.
I never thought of it that way. Thank you for stating it so well -- it helps clear away dangerous doubts.