There are three distinct types or stages of "love":
- Lust, or erotic passion
- Attraction, or romantic passion
- Attachment, or commitment
When all three of these happen with the same person, you have a very strong bond. Sometimes, however, the one we lust after isn't the one we're actually in love with.
When we're teenagers, just after puberty, estrogen and testosterone become active in our bodies for the first time and create the desire to experience "love." These desires, a.k.a. lust, play a big role both during puberty and throughout our lives. According to an article by Lisa Diamond, entitled "Love and Sexual Desire" (Current Directions in Psychological Science, vol 13 no. 3), lust and romantic love are two different things caused by different underlying substrates. Lust evolved for the purpose of sexual mating, while romantic love evolved because of the need for infant/child bonding. So even though we often experience lust for our romantic partner, sometimes we don't -- and that's okay. Or, maybe we do, but we also lust after someone else. According to Dr. Diamond, that's normal.
Sexologist John Money draws the line between love and lust in this way: "Love exists above the belt, lust below. Love is lyrical. Lust is lewd."
Pheromones, looks and our own learned predispositions for what we look for in a mate play an important role in whom we lust after, as well. Without lust, we might never find that special someone. But, while lust keeps us "looking around," it is our desire for romance that leads us to attraction.
While the initial feelings may (or may not) come from lust, what happens next -- if the relationship is to progress -- is attraction. When attraction, or romantic passion, comes into play, we often lose our ability to think rationally -- at least when it comes to the object of our attraction. The old saying "love is blind" is really accurate in this stage. We are often oblivious to any flaws our partner might have. We idealize them and can't get them off our minds. This overwhelming preoccupation and drive is part of our biology. We'll go deeper into the chemicals involved in attraction in The Chemistry of Love.
In this stage, couples spend many hours getting to know each other. If this attraction remains strong and is felt by both of them, then they usually enter the third stage: attachment.