Here is more on the story:
http://www.javno.com/en/croatia/clanak.php?id=148109
By the sounds of it, people did notice she was missing and contacted the police back in 1991.
I was right though, the utilities are all on one bill.
Some people also claim that she was a schitzophrenic. Others thought that she left and the apartment just remained vacant over the years. They were tired of paying the bills for it and wanted to claim it.
She was also an old lady (84), so it is entirely possible that if she had no children, all of he other living relatives my have been dead. She could have been the last of her line.
List source also says that she was reported missing back it 1966:
http://www.ananova.com/news/story/sm...=news.quirkies