Sotto, I disagree - quite apart from the idea of stunning an assailant with a bright beam, in close combat a flashlight makes an excellent defensive weapon. Instead of smashing an assailant's nose or gouging his eye with your fist and fingers, you can add a debilitating hard knock to their temple, jaw, cheek, nose, eye, teeth, throat etc etc, any of which should give you time to cave one or both knees, which will give you time to get away.
All it takes is an attitude of aggression, and the will to beat your opponent. Since they're out to rape, rob or kill you, hopefully you have the will to end their efforts.