Ive just completed the quest Dark Revelations for the Dark Brotherhood. I went to hand in the quest but i had a full inventory so i cancelled and went to the workbenches to deconstruct things to make space for my reward but when i got back she was gone. The arrow is still there showing her location.
Ive tried reloging and also tried leaving the sanctuary and coming back in but neither have fixed the issue.
Cant progress any further in the DB Storyline now.