I dreamed about my sister again

The dream I had about my sister also had some of my "sleuthy" friends, too.  I have no idea what it means.

I remember helping to keep away a friend of mine (her kids were in the dream, too; we'll call her A.R.) away from someone who was trying to hurt her, assault her.  I don't recall kicking anyone's ass, but I know I did my very best to protect them.  When I thought they were safe, I left for another place.

I was walking along a sidewalk with someone when I ran into my sister.  She looked a wreck and really upset.  Just as she began speaking, a male voice said to me (I know I was with a guy, I just can't place the voice or face), "Hey, it's your sister, A----."

I was upset with him for talking while she was trying to talk.  I looked him in the eye (still can't tell you what he looks like) and said, "I know it's my sister rape."  And that's when it hits me (in the dream); my sister's been sexually assaulted this time and brutally.  I tried to back pedal from what I'd just said, and she looked at me with a glint in her eye.  She smiled her crooked smile wearing black/red lipstick.  She tried to bring me back to the place where she'd been assaulted.  I wouldn't go in with her.  I tried to keep her from going back.  She wouldn't leave with me.

I remember feeling hurt and her yelling at me for not coming with her to "join the fun."  I remember going up to the window where I'd heard her and whispered something like, "Well, at least I'm not going to die a whore, like you."  I ran off as she came to the window screaming at me again.

I woke up wanting to help her.  It took me two days to gather up what I could to type that out.    I have no idea what to make of this dream.  I feel awful.  I feel terrible.  I love my sister and I'd do everything in my power to keep her safe.