I have a huge problem with my kitty?

i posted this before but im posting it again becuase i need more answers. im going to make this as short as i can but i really hope someone can give me some advise. My kitty is usually thing friendliest thing out but the last 2 weeks she has been skittish and scared of every noise she doesn't really play anymore all shes does is hides and sleeps i didn't think too much of it i just thought she may be getting out of the kitty stage but about 3 days ago i was running to the phone and she ran in front of my feet and we collided it wouldn't have hurt her becuase i didn't really kick her she pretty much just skidded on the floor this had happened a few times and its never really bothered her but this time she started shaking and when i picked her up she sort of played dead like she was really scared of me. Anyway i found out that my old housemate who no longer lives here admitted to hitting her a couple of times he said that the kitty bit him so he smacked her twice over her head and threw a shoe at her and he has also admitted to hitting her with a wooden spoon i was so mad and so upset i was in tears i felt so bad that i didn't know but i honestly didn't think he would do something so horrible so i rushed her to the vet for a check up and the vet said she was physically ok just extremely shaken up and he said to just give her a few days. I have been giving it time and she is still the same she is scared at every noise and she is even terrified of me and it breaks me heart will she ever recover from this and what can i do to help? i can tell shes not the same becuase usually when i pick her up and look at me she has big wide eyes and is contently licking my nose but now when i pick her up and look at her she goes still and her ears go right down and back and her eyes are like little slits it makes me so sad