I didn't know it was Maria Schneider who played the role when I saw the movie, I hadn't recognized her, or more likely I hadn't even made the link. I only had seen her in the movie Last Tango in Paris, after which she suffered greatly. RIP to her.
In the book The Wide Sagossa Sea, Bertha was not mad , but beautiful and intelligent. She went mad after she went to England. Before that Edward and Bertha had a good relationship.