Joyce & her beating

The ONLY thing I have a question about is why she just stood there getting punched in the face. Not when she was on the floor, but when he first started. It would be natural instinct for someone to at least wince while being punched. I mean, at least the 2nd or 3rd time before she fell. It was believable that she didn't try to escape. Totally unbelievable she had basically zero reaction to being punched.