Did Hitchcock blackball Tippi Hedren?

According to Tippi Hedren, he did. She has publicly stated that Hitchcock ruined her career. Ms. Hedren has stated to the press that Hitchcock was obsessed with her and tried to control her life. After the filming of Marnie (1964), she told Hitchcock that she could no longer work with him. However, Hitchcock still had her under contract, and he refused to let her work with anyone else. Although, several directors and producers wanted to work with her, Hitchcock didn't let her out of her contract for more than two years.