It’s too common for a woman to be alone with strangers for her to make a confrontation each time. Think about a shopping trip from a woman’s point of view. Getting to the car, carrying things, being smaller than half the population, children, etc.
Plus, a man will leave you alone until you look nervous - then he gets interested. His interest is always innocent, even helpful, until it’s not.
Had he known she had a gun and was prepared to use it, he may have opted to get off on another floor. Or to vacate the building entirely.