I can't count how many times I've talked to couples after some kind of disagreement where no one has said "I'm sorry". So often, it seems easier to walk away from an uncomfortable situation than to face it. While I often stress the importance of taking a 'time out' in a heated moment, taking accountability is way more integral to the health of your relationship.
Read more about the importance of saying 'I'm sorry' in my article for MeetMindful.com.
http://www.meetmindful.com/articles-difficult-times-the-importance-of-im-sorry/