One spouse in a married couple seeks to bring about the death of their partner.

Examples:
In nightgallery2x19b "Stop Killing Me", Francis Turchin arrives at the local police station to explain that her husband is actively murdering her by a most unusual method: By making frequent remarks about killing her he is instilling in her such anxiety that she will, within a week no less, fail to pay attention to her surroundings and suffer a deadly accident.

References:
https://en.wikipedia.org/wiki/Mariticide https://en.wikipedia.org/wiki/Uxoricide