tears are like the blood of an emotional injury. When we get hurt physically our body bleeds to clean the wound and the blood also creates the protective space for the injury to come together and heal. Tears are the emotional equivalent. They wash out the emotional injury and create a space for healing. Some times, depending on the injury you have to flush the wound or allow for it to drain longer term to heal correctly and tears are the same way. Sometimes one good cry flushes everything out and healing can happen quickly. With deeper injuries healing has to happen from the inside out and so tears happen on and off for a longer time.