Survivor's guilt

Survivor guilt was the mental condition that results from the appraisal that a person has done wrong by surviving traumatic events such as combat or disasters. The effect of survivor's guilt depends on the person’s own psychological make-up.

Apparent sufferers include Bernice Summerfield (NA: Love and War) and the Doctor's ninth incarnation. (DW: Dalek)

The Doctor's eighth incarnation insisted that he was psychologically incapable of experiencing such a thing. (EDA: The Gallifrey Chronicles)