Not completely sure I'm understanding this. You're suggesting that home invasions involving rape don't happen? A rather famous case comes instantly to mind, though I've heard of many, many others over the decades. Ever heard of the Petit family being viciously attacked, the wife and daughter murdered, the husband/father being seriously injured and barely escaping while his family was being raped, tortured and killed? Makes for some rather horrific reading.
https://en.wikipedia.org/wiki/Cheshire,_Connecticut,_home_invasion_murders
And then there was that police detective in California, called the 'Golden State Killer' at the time, whose specialty was using his authority, his badge, to enter homes, then to restrain any men, put dinnerware on their backs and tell them that if he heard plates falling he'd murder their loved ones, after which he would proceed to rape and murder their female family members. Lovely fellow. They finally caught him as a feeble old man, long after his lengthy crime spree, thanks to some relative getting a DNA ancestry test done.
Richard Ramirez was another infamous creep in California, a spree killer who seemed to love the suffering of his several victims.
In any of these cases a pistol or shotgun or whatever handy firearm in the hands of the residents might have proven effective in preventing their victimization. But perhaps you weren't suggesting what it seemed you were suggesting and you agree? Hard to tell, because if you're implying home invasions leading to rape and often murder don't happen, dude, you're living in unicornland.