How do you know when you're in love? How do you even know when you're in a "Relationship?" How is a capital R "Relationship" different from all the other "relationships" of life?
Let's start by looking at relationships in general: friends, lovers, acquaintances. If we put these on a spectrum according to the amount of emotional investment in the relationship, we discover that they fall into six fairly discrete groups, the six levels of relationship*.
1. Acquaintanceship Acquaintances are the people that we don't really know; we just happen to bump into them in the course of daily life. Cab drivers, store clerks, most co-workers. What distinguishes this group is that we don't choose them in any way. We choose something else that causes us to be in that place at that time (the job, the store, the taxi) and we meet these people along the way. We have contact with them by chance, not by choice. Acquaintanceship is by far the largest of the six groups, and this is where all our relationships start. If we particularly like someone in this group, we may choose to invite them into the next level.
2. Companionship A companion is someone we seek out in order to share an activity with them. At this level, the activity is still more important than the person. For instance, suppose that I'm a tennis buff. When I want to play tennis, I start calling up my tennis friends. If the first one can't play, I say thanks and move on to the second one. I go down the list until I find someone who has time to play tennis. The people are interchangeable; it is the activity that is primary. This is not an insult to anyone. We all know that our relationship centers around tennis because that is the only time we see each other. If I come to like one of my tennis buddies particularly, I may want to invite them into a friendship.
3. Friendship Now the priorities are reversed: the person is more important than the activity. Suppose I want to see my friend Bob. I call him up and say "Can you get together today?" If he says yes, then we negotiate what we want to do together. Maybe we'll see a movie, or take a walk, or eat dinner, or even play tennis. What makes us friends is that we are getting together to enjoy each others company, rather than for a particular activity.
Notice that in these first three levels, there is no commitment to any further contact in the future. These levels are based on choices you make for the present moment only: accidental contact (no choice), choosing the activity, and choosing the person. The next three levels are based on your priorities over time and reflect deepening degrees of commitment.
4. Committed Friendship Time is the new feature here. Now there is an agreement to continue to be available to each other in the future. This is not an exclusive relationship. It is expected that you will each have other committed friends as well, but there is a commitment to continue this friendship for the foreseeable future.
5. Primary Friendship This is your "best friend". This person is not only a committed friend, but the most important one, the one you put first when you have to choose. Priority is the new feature here. You may change best friends from time to time, but there can be only one person at a time who has priority over all others.
6. Life Partner To priority we now add permanence. Your life partner is assured that they are not only the most important person in your life, but that they can depend on holding that office for life. Otherwise, we're back to level 5. This is why the marriage vow is "until death do us part" instead of "until we change our minds."
These two conditions (priority & permanence) make this level of relationship uniquely powerful for us emotionally. It is this relationship which most stimulates our unconscious hopes and fears and fantasies. What makes this level of relationship so powerful is its resonance with our first love affair, the one we had with our mother when we were an infant. She was our first "one and only love" and that relationship remains in our unconscious as the prototype of all future love affairs. Each new love stirs those old hopes and fears and shapes our feelings in the present. This level of relationship stirs our deepest wounds, offering us both the hope of healing them and the fear of being hurt anew.
And, of course, this is typically the relationship we are referring to when we say we are "looking for a Relationship." We already have a "small r relationship" with the friend or acquaintance we are talking to, but it is the "big R Relationship" we mean when we say we are looking for one.
Notice that having sex does not determine what level of relationship you're having with someone. A person can have or not have sex at any of these levels. For instance, at an orgy a person might have sex with someone simply because they happened to be within reach. This is sex at the acquaintance level. When someone goes to a pickup place to find a partner for a one-night stand, they are having sex at the companion level. Sex can also take place within the context of a friendship or a committed friendship or a primary friendship.
However, adding sex to a relationship can be confusing, because the touching and tenderness and pleasure of sex also recreate the infant-mother experience and stir up our unconscious hopes of once again finding that one-and-only love connection. So adding sex can easily skew our perception of the relationship and make us feel like we are now in level 6, when in fact we're not.
I hope that using this model of the levels of relationship will help you see more clearly and navigate more easily the various relationships in your life.
* This model is based on one presented by Terry Gorski in a talk on relationships. I have modified it somewhat, but I am indebted to him for the majority of it. I do not know whether it was original to him or based on someone else's work.