Some people defend their partner's shortcomings while others don't.
Psychologists at the University of Toronto explain that whether or not someone protects a partner from the negative implications of comparisons depends on the degree to which they view themselves and their partner as one unit.
This phenomenon has been dubbed "self-other overlap". People who were high on self-other overlap would attempt to protect their partner and minimize the threat by rating the trait or skill that they compared their partner on as less important.
Furthermore, these people maintain positive views of their partner in spite of unfavorable comparisons, which has positive implications on their relationship.
The studies provide the first evidence that people do compare their partner to others with significant consequences for the relationship.
People who are low in self-partner overlap have difficulty maintaining positive partner perceptions following threatening comparisons of their partner to others. This may be a key source of stress and conflict in people's relationships.