Stephen Hawking cheated and left his wife of 30 years who supported him through his illness, to marry his nurse, who was married to the guy who built his speech device. The second marriage ended in drama. His 2nd wife was apparently abusive and maybe broke his wrist.
Staff noticed that Stephen hawking had bruises, cuts and a broken wrist, without any explanations. The police got involved into their chaotic marriage to investigate.
Staff described their relationship as controlling and intense. There were claims that she left him in the garden under the sun for hours. She kept him away from his family, until they were completely cut off (Which involved his children too)