You thought the tearful goodbye was bad, but now you realize it pales in comparison to the challenge that remains -- keeping your relationship alive while you're away from your significant other for the summer.

Welcome to the long-distance relationship, a reality for many who descend on the area for summer jobs and internships. You're not alone: Around 7 million couples in the United States live in different Zip codes -- 3 to 4.5 million are dating and 2.5 to 3 million are married, according to the California-based Center for the Study of Long-Distance Relationships. Luckily, being apart can actually prove beneficial to your love life. "It's a time of crisis for your relationship," says Helen Fisher, anthropologist at Rutgers University and author of "Why We Love." "And it's either going to tremendously improve it or it's going to completely suffocate it."

Here are five ways to ensure your relationship is still breathing come September:

1 Establish rules.

How often will you talk on the phone? How many times will you visit? Who's going to do most of the traveling? More important than the answers is the need to agree on a game plan. If you haven't already discussed logistics, bring them up now to avoid surprises and wasted time obsessing over the details. The answers will be driven by concrete factors such as the distance between you, your financial situation and your living arrangement. "My fiance won't end up coming here because I'm sleeping on someone's couch," says Heather Goldner, 24, a law student who left Philadelphia for a summer job at the District's National Women's Law Center. "That's why I brought my car down, so I can drive back and forth."

2 Up the chatter.

It's true that nothing can replace physical contact. "When you massage someone, the levels of oxytocin go up in the brain," says Fisher, "and oxytocin is one of the chemicals that drives attachment." But Fisher, who is in a long-distance relationship herself, thinks that verbal communication might have a similar effect. When you chat, share the day-to-day details. Don't fall into the trap of not bothering to discuss the mundane. Think about your relationship when you were still living in the same place -- some interactions were important, but most were reassuringly boring. Maintain this balance, and you won't skip a beat. For Goldner, that means a lot of time on the phone. "Today, I already called him three times, and once was just to say that I found the Trader Joe's," she says. Today's high-tech world brings multiple options to try: e-mail, text messages or even a webcam.

3 Be romantic.

"Barriers tend to intensify romance," says Fisher. "It's called the Romeo and Juliet effect. I call it 'frustration attraction.'" Play this up with gestures that remind your loved one not only that you still exist, but that you are the most thoughtful, attentive person they'll ever meet. Brad Sherwood, 23, left his sweetheart in Sacramento when he came to the District for a graduate program at George Washington University. The first time she visited, he couldn't meet her at the airport. "I sent a driver to pick her up and to meet her with roses," he reports. He also booked the honeymoon suite at the Wyndham Hotel downtown. Outmoded means of communication, like ye olde handwritten letter dabbed with your favorite cologne, can be one of the most effective weapons in a long-distance relationship. Or, when you visit, hide notes to be discovered later. Of course, all of these deeds pale in comparison to the best, most meaningful gift of all: the surprise visit.

4 Get busy, but don't get busy.

While it's advisable to make new friends and have an active social calendar, remain sensitive to that brand of human frailty known as jealousy. So call when you get home from a night out, and tell your significant other, "I really wish you were here to meet my new friends." Avoid talking to your faraway mate too much about one person. And don't kid yourself: Spending all of your time with one person can easily lead to temptation. Make sure you hang out with lots of people.

5 Reunite -- and

reconnect.

Seeing each other after a long separation can seem awkward at first. That's because separation drives up passion and drives down intimacy. You're feeling so excited when you greet each other at the train station that your escalated dopamine levels have triggered a fear response, characterized by anxiety. Fisher prescribes physical contact and deep conversation as a way to revive the relationship. Of course, all of this canoodling worsens the goodbye. Some coping strategies: Before you leave, agree on a time and place for the next visit. And don't give in to the common mistake of picking a fight right before your partner leaves. Realize what's really going on -- you're not angry that he left the seat up, you're angry at the distance.

Caroline Tiger

Freelance writer Caroline Tiger is the author of "The Long-Distance Relationship Guide: Advice for the Geographically Challenged" (Quirk Books, $12.95).