Hakim al-Umma Mawlana Ashraf ‘Ali Thanawi (may Allah have mercy on him) said,

“The root cause of unity and accord is to accept an individual as the leader and others agree to follow him.  In a group where everyone claims to be equal to others, without any distinction of leader and followers there can never be unity at all.”

Tohfa zojain, page 46

This rule also applies to marital relationship.