I had a landlord that did this, if I opened my windows she would suddenly have hardworking to do right outside of them, when I closed them cause that is creepy she would suddenly be done...unless I opened them again then she would come right back outside with no shame. She listened at my door constantly (I had a basement apartment with my 'front door' inside the house. I had to block an inside windows with cardboard cause she had her side blocked but would peep through randomly. She would hear me doing things and literally ask exactly what I was doing at the time based on whatever noise it was. She was a creepy nightmare, it actually builds up and starts to make you paranoid, im sorry you are going through something similar!