Do you remember how it felt when you were first falling in love? Or maybe you don’t have to remember because you’re lucky enough to be in that heightened state right now. Either way, the experience is intense, delicious, magical, something to be enjoyed to the fullest.

All your physical and mental juices are flowing, and the experience is literally intoxicating. In new relationships sex tends to be exhilarating, and most new couples are eager to make love as often as possible. Nights may be long – with bouts of lovemaking interspersed with deep conversation and no concern about feeling sleep deprived. Those who are in this elevated and almost manic state are sometimes described as being in the throes of new relationship energy (NRE).

NRE can be a very heady and enjoyable state, and there’s no reason to deny yourself the intensity and pleasure that accompanies it. As long as you remain mindful of the fact that it is temporary and something of an illusion, you’ll be able to revel in it without being consumed by it. Similarly, remembering that the intensity will not last will make it much easier to transition from being in a new relationship to being in a longer-term one. During this stage, the novelty of discovering a new partner, exploring and enjoying that partner’s body, can create its own momentum. The same intensity is sometimes felt in casual sexual encounters. Novelty can be very alluring and can function as a powerful aphrodisiac.

NRE usually propels people for six months or so, but for some its effects can last as long as two years. As Helen Fisher has argued in The Anatomy of Love, NRE is (for the most part) a neurochemical phenomenon. It is very easy to make all kinds of promises and fantasize about having a life together when you are in this altered state of consciousness. Ironically, this is actually the worst time to decide whether this is the person you want to be with for the long term. Knowing that NRE is influencing (and possibly impairing) your judgment during this early stage can provide you some protection against being overwhelmed and making less than optimal decisions or promises that you’ll end up regretting.

The emotions you feel during this period may seem like love, but they are probably better described as infatuation. Six months is not long enough to develop a real relationship and get to know another person. More often than not, your ideas about your beloved during this period are based on limited knowledge, projections, and fantasy. As infatuation fades and you start to gain a deeper knowledge of this other, you may realize that the person who captivated you is not the paragon of virtue that you imagined. It’s easy to feel misled and deceived when this happens, but in most cases the deception is self-deception, and the disappointment is rooted in the other’s inability to live up to your fantasy.

So love in the first six months is often frenzied, a kind of hallucination. Because everything is so heightened, it’s a very exciting time, and it can be filled with drama, especially if you’re afraid that the object of your affections and desire does not reciprocate. While this intense emotion may prove to be a foundation for a calmer, more balanced relationship over time, the drama that gets associated with new love, and especially with unrequited love, is not likely to be sustainable in a long-term partnership, even a passionate one, and we suspect that few people would want it to be.

Modern popular culture conditions people to believe that new is better, that excitement, intensity, and fervor are equivalent to depth of feeling. In fact, intensity and depth are two radically different things. When you are in the throes of NRE, your feelings, though real, can’t have the depth that they would have with someone you know well. There’s a difference between falling in love and loving. You may be smitten by someone, or may have experienced “love at first sight.” This isn’t love; it’s chemistry, though it’s often the case that what triggers your response – whether it’s vocal quality, a particular scent, a way of moving, hair, eye color, bone structure, or anything else – is deeply rooted in your biology and past attachments. This kind of deep sense of connection is important, but it is by no means a guarantee that you are truly well matched. The qualities that are revealed over time are the ones that are more significant in terms of long-term relationship satisfaction.

Some people feel disappointed or disillusioned as NRE starts to dissipate. This can lead to a breakup, especially among those who conflate love and infatuation or crave the intensity that NRE engenders. For others, the change is less dramatic, and the transition from infatuation or what psychologists call limerence to enduring love feels natural or even seamless. The end of infatuation is the first major turning point in any partnership.

The next turning point in many relationships takes place when people move in together or get married. Challenges relate to the shift that takes place when people stop dating each other, having separate lives, and getting together when it’s mutually desirable and convenient to do so. As Esther Perel observed in Mating in Captivity, there is a tension between the domestic and the erotic. It would be foolhardy to pretend that this tension is not real. The person you are dating is a lot more mysterious than the person with whom you wake up every morning, whose odors, illnesses, and changes in mood become a part of your everyday existence.

Some may think this is a pessimistic view of love and long-term relationships, but we prefer to see it as a realistic and empowering one. Recognizing these biological facts makes it possible to act in ways that will strengthen your bond and keep your erotic connection vibrant as you transition from infatuated to enduring love or from dating each other to being a couple. Even if you’re a long-term couple, we encourage you to keep on dating each other.

Whether you are brand-new lovers or you have been together for years, it’s crucial to become skilled at relating both in and out of bed. As time goes on, you may have to become more active in choosing to remain sexually engaged. While this may take effort at times, your knowledge of each other, your shared base of experience, and the goodwill you’ve built by repeatedly demonstrating your dedication to having a great erotic life are likely to enrich both your relationship and your lovemaking.

Excerpted from Partners in Passion: A Guide to Great Sex, Emotional Intimacy, and Long Term Love by Mark Michaels and Patricia Johnson, $21.95, 978-1-62778-028-5, published by Cleis Press, www.cleispress.com.

Mark A. Michaels received a J.D. from NYU and Masters degrees in American Studies from NYU and Yale. He has written for scholarly and legal publications and for the stage and has had his work produced off-Broadway. In the late 1980s, he served as literary manager at New York City’s Roundabout Theatre Company and then was staff attorney for a Native American legal organization. Patricia Johnson spent many years as a professional operatic soprano, performing leading roles at some of the world’s premiere venues, including an appearance on PBS’s Live from Lincoln Center. She and Michaels have taught and lectured throughout the U.S., in Canada, the Caribbean, Europe, and Australia. Their books: Great Sex Made Simple, Tantra for Erotic Empowerment, and The Essence of Tantric Sexuality have won awards and received critical acclaim.