I had a stalker when I was 16, He started calling the house making all kinds of comments toward me and what he would like to do to me. I had not a clue who he was. This was before we had caller ID and all that other wonderful stuff we have now. It went from just random phone calls, to this guy calling and telling me how much he enjoyed watching me change class at school. To he couldn't wait to see me wear that outfit I had bought at Wal-mart that afternoon. He acted like I should know who he was and would get very upset when I would ask him who he was. The police was contacted and my family was out for blood.
It took us almost 2 years to figure out who this guy was. Come to find out he was a 40 year old man, who ate breakfast every morning at the same place I would stop and get my breakfast before school. I never so much as said boo to this guy. When he was found out, he no longer saw the reason to hide his feelings. He was everywhere! School, after school, and in town. I couldn't get away from this guy. The law at the time, would allow the police to arrest him. He would get out on bound in a few hours and be right back where he left off. He knew this, as he told my mother if we had him arrested he would get out of jail long enough to kill me. To quote him "I will blow her head off"!
He later left the community, but I did run into him a few years later. I was with a group that wouldn't let him get to me. But still to this day, he scares me to death.
My point is, she could have very well never met, knew or had any contact from this guy until that morning. She could have given him a smile, or said hello to him in passing and this guy could have taken it for way more than it was.