For the intents and purposes of this essay, I will define a "ritual" as a planned set of symbolic actions. Otherwise, I am going to end up writing a treatise and I don't want to. As you will notice, I'm not being extremely scholarly about this essay, either. If we're going to talk about the ways rituals help us, then I might as well explain the one I am performing right now. One of my rituals is to take material that I read and see how it integrates into my already acquired knowledge and personal experiences. I am what some call an "experiential learner". My ritual of ingesting information by using it in the form of an original writing, organizing it in some way, or just finding a practical use for it in my own life, helps me to retain and understand the information better. This is really the purpose of rituals--to help. Whether by controlling anxiety through organization, recognizing achievement, dictating social actions to make things go smoother, or creating social bonds, rituals are usually established as a helpful mechanism for life's changes and challenges.
Separation can be either voluntary (such as becoming a graduate or a bride) or non-voluntary (such as a griever of a loved one who died). In this phase, the major participants of the ritual become marked as different from the rest of society. While mostly symbolic, this separation can also be a physical one. In many cases physical separation serves a purpose. Grieving, depressed and ill people need to conserve their energies to deal with their tribulation. Graduates, engaged couples, presidents elect and students like myself need time to organize and plan without distractions.
Transition is the formal part of the ritual where the participants change from their former lives to their new lives. The grieving say goodbye to the deceased. The bride and groom become wife and husband. The undergrad becomes the graduate. In other cultures, a child becomes and adult. And I become more educated.
Healing rituals have a few other commonalities. The first part if the "naming" of the problem. Talk to any person who has finally gotten a diagnosis for an illness, and you will find that a sense of empowerment and relief often comes with it. (I had a friend who used to tell me that I was the only person she knew, who was happy to find out I was clinically depressed.) There are obviously some exceptions to this, but in general it is true. However, the naming of the problem must come from someone the person trusts or it's not going to help at all. (Like the fictional Dr. House who refuses to believe that he has lupus.) In a way this is the medical part of the separation ritual. By having a name for your problem, you become part of a definite and separate subgroup from the rest of society. Part of the transistion phase of a healing ritual includes many common steps of recovery, helping the participant to live a healthier life. Effective healing rituals help to create stronger support systems for the participant, making the return to daily life a more stable one.