His wife died of blood loss from going to the incubation room to beg her husband to not kill Mariko after all. As much as I understand how tough his situation was, it's strange that he was so attached to Nana yet he'd go as far as to attempt to shoot Mariko down. She even outright told him that she really did want to be loved by her father regardless if he wanted to kill her...
She doesn't care about living anymore.
