I cannot speak for your friend, but for me, sometimes I would wish people didn't know. I've had friends who are perfect supporters, but mostly I've had friends who want to be supportive and don't know how.
It's hard when you're dealing with the immediate aftermath, the shame and stigma, it's hard to think your friends know that you were that vulnerable, or that you gave up. When I was raped, I gave up. I let my head hang upside-down over the armrest of the couch and I watched the movie we put on until it was over. Many of the people I wanted to confide in didn't understand that, and I wished I hadn't told them anything. I wished I could pretend that none of it had happened. I didn't want to see myself as a victim, and I didn't like that my friends saw me as a victim or treated me like a weak person.
The things my friends have done for me that was most meaningful was to just hear me. Before we were together, I mentioned to my current partner that surviving rape was the reason I went into my field and how it shaped my spiritual values. He said that was surprising, and thanked me for sharing with him. About a year later, he expressed an interest in hearing my story, if and only if I wanted to share it with him. I said I was relieved to hear him say that, because I wanted to tell him, and when I told him he thanked me for confiding in him and didn't ask any questions. All he did was offer support.
I would offer you this advice: Don't ask questions about the rape or the PTSD. Ask your friend out for lunch and then ask her what she's been doing for fun or how work is. Make a point to be present for her and to talk about things in her life unrelated to the rape. If she brings it up, listen, and thank her for trusting you with her feelings. Let her know you will always be there to listen if she needs you. Then tell her what you think about a new movie, or ask her if she's heard that cool song.
