De Villota, who lost her right eye in an accident last year, was in Spain promoting her autobiography Life is a Gift ahead of its release on Monday.
"She had such a spirit for life and what she came through was a testament to her strength of character and her positive outlook," BBC Sport quotes Wolff as saying.
"After the accident, she was so behind me and had such a lust for life. She was so happy to be alive and that she'd survived it. She had so many great plans for the future. She was just an incredible lady."
F1 teams and drivers have paid tribute to De Villota following the news.