As I've taught my wife, just make sure you empty the clip.
There is nothing so convincing than a woman who keeps pulling the trigger until she hears "click, click, click" and runs out of bullets defending herself.
Aim for center mass and don't stop pulling the trigger until the the magazine is empty.
At that point all she has to say is "I don't know, I was so afraid I just kept pulling the trigger until I heard click, click, click."
Well then make sure your wife reads this story, especially this part:
"Then Smith positioned the revolver's barrel under her chin and pulled the trigger in what he described as a "good, clean finishing shot" meant to end her suffering, he said."
Yep Smith should be one of your heroes. Someone for you and your wife to look to and emulate. Maybe you can send him some of your advice when he is sitting in that jail cell.