A relationship is built upon five pillars.
The first pillar is TRUTH. For a relationship to work and abide there must be a healthy respect in each person's life for the truth. For the heart to draw together toward another heart there must be a communion of truth. Most relationships have special areas of truth that are shared. While the friendship may exclude other truths the relationship must be built upon an understanding and communciation of certain truths that are expected to be protected and maintained.
The essence of truth between two hearts is very simple - unlimited and unconditional access to the heart. This means you let the person inside you without barriers. This means the mind is not allowed to edit the person as they approach the heart, this means the emotions are not allowed to rule as they prophesy this person's failure with your heart. You let them in. And they see you for who you really are. They are able to distinguish your heart from your mind and feelings. They know your heart. In some ways, they know you better than you know yourself.