Reading the news reports carefully, it looks as if the female pilot's initial intention was to alert the company that one of their pilots was a serious problem. She didn't intend to report a rape and get him charged. I imagine she thought the company would investigate and take appropriate action.
Instead, the company effectively suspended her for six months and did nothing at all about the male pilot. I imagine they hoped she'd get fed up and leave, chalking it up to experience. When she didn't, they were forced to allow her back to work, where she discovered that this man was still flying, and still potentially being rostered with female pilots. Perhaps even herself.
It looks as if, at that point, she realised that she would have to go to law and expose both the pilot and the company in public.