We collected her from the previous owner 5 days ago and she was terrified. I showed my girlfriend how to communicate with the cat and after 2 days of her living with us, the cat was completely different, playful, affectionate, etc. She spends more time with my girlfriend then me as I'm at work in the day and Lilly follows her around, playing with her completely at ease. now the cat has started to hiss at me and shy away from me when I get home. I continue to feed her, play with her but once that is over the cat hides away and hisses again. What should I do?