Why does she frown every time she sees you and how can you make her stop?

She frowns because either she's nearsighted and is trying to pull a focus (unlikely), or she doesn't like you or something about you. She probably stops frowning as soon as you get out her sight. My free advice is to not waste your time trying to start something with her. Instead, direct your efforts to finding someone who meets your basic requirements (say, no eye in the middle of her forehead), and smiles when she sees you. Leave the hard challenges for Rubik's Cube or World Of Warcraft. Good luck - really.