Had a dream that my grandpa raped me...

This is the most disgusting dream I have ever had. It starts of with me finding a video of my grandpa molesting me when I was like maybe 9 years old (I've never been assaulted by him or any other family member but I do remember my mom telling me not to wear shorts around him even if it was hot weather) and I showed the video to my parents and they did nothing? I'm genuinely so confused as to why I even had that dream I just don't know what that could even mean.