On the internet I read an article where a journalist mentioned that Barbara had slized her wrist at some point. She certainly never sliced her wrist in England. I can't imagine that she did in Hong Kong. She was a very public figure there. People would have noticed immediately if she had harmed herself in any way, especially with all those photo shoots she had.
The only explanation I think that explains the cause of the story of the wrist slashing, is that Barbara hands and wrists were marked with scars. Working with the hot fat in the fish and chip shop left sometimes burning scars on her hands and arms. I tried to look at pictures on the internet if I could see these scars on het hand but I could find very few pictures of Barbara where she is showing her hands. Which doesn't surprise me as Barbara didn't have "lady-like" hands, here hands were large and the fingers were not long and thin.
Maybe a journalist noticed those scars and assumed they came from wrist slashing. A bit far fetched but that is all I can think of to explains this theory. But like someone wrote to me "Reporters are the most creative people".
(thanks to Natalie for the translation)
This picture of Barbara shows clearly the marks on her arms, caused by the hot fat from her work at the Fish and Chip shop