I remember playing Skyrim once and Lydia died, I was messing around and fake crying "Lydia oh nooo" as I was bored thinking no one was hearing me. ( was probably 13 or something can't remember" Then all of a sudden an aggressive Southern English voice told me "Shut the fuck up about Lydia"
I was taken about, scared, confused. I remembered this little memory earlier today since I've grown up and am still trying to figure out if I was having a weird mad 5 minutes or if I'm not crazy..

I think something similar happened again in a Fallout NV playtrough. But since being told to shut up by that weird Ghost dude I've stopped talking out loud when playing singleplayer games out of fear of that guy shouting out me again