The person who:

• was the spouse of the deceased at the time of death, had not been living separate and apart from the deceased for 90 days or more at that time because of the breakdown of their relationship, and was not the spouse of another person on December 31 of the year of death or, if he or she also died during the year, on the date of his or her own death, whichever came first; or
• was the last person to have been the spouse of the deceased during the year, where this person also died during the year and, at the time of his or her own death, was the spouse of the deceased and had not been living separate and apart from the deceased for 90 days or more because of the breakdown of their relationship.