I think sometimes folks don’t think straight in high stress situations. Maybe she just wanted him gone - not good thinking.
I remember when I was a Freshman at UT, Police Officers came to all the girls dorms and offered basic self-defense training. (I think there’d been a rash of rapes and almost rapes) No 1 was don’t try to use a weapon that can be used against you, because it will be. They talked about how to always carry our keys in our hands with one sticking out between our ring and middle finger to be used to poke into an eye if grabbed. Also taught us how to break a one hand wrist grab, etc. The number one thing we were told was travel with another and always, always (alone or with others) be acutely aware of your surroundings. And Run Away.