Some of what I'm going to say here will be more or less a restating (or, perhaps less kindly, "rehash") of what was said before, but being that I've gone through both an unsuccessful long distance relationship {from here on referred to as an "LDR") and a successful (so far, knock wood) one, I like to consider myself somewhat of an authority on the subject. That being said, here are a number of helpful do's and don'ts on how to get through an LDR without getting your heart broken.

I should point out that some of these tips apply to LDRs that begin by meeting over the internet, when some semblance of a romantic bond begins without benefit of meeting in the flesh first.

DO understand that frequent and regular communication is essential. Several months may pass before you see your significant other (from here on referred to as your "SO") in person, learn to rely on the telephone, e-mail, and instant messenger programs such as ICQ or Yahoo! to keep in touch. During the ten months when 2,500 miles separated me from my current SO, we made contact with each other in some form every day, even if it was just a text message.

DON'T make any sort of declarations of love, or even where your relationship formally stands, until you've met in person. Personality may be more important than appearance, but chemistry, that physical spark is still necessary to maintain a healthy relationship. It's where the line is drawn between being "just friends" and being "something more." It's not uncommon for that spark to fail to carry over into "the real world." This can be extremely painful, for both and you and the other party, if you've already convinced yourself and him or her that you're in love and a couple. It's not superficial to be unable to fake physical attraction to someone you genuinely care about, it's human nature.

DO be on the same page with your SO about the status of the relationship. If you think it's gotten to the point where you're no longer interested in dating other people, don't just assume your SO feels the same way. One issue that frequently comes up in LDRs is the belief that the parties involved should only be considered in a relationship when they're actually together. Your SO may not be comfortable with declaring you a formal couple until you're around each other all the time. You need to know this. It goes back to the most important element of a successful LDR: communication. You may have to ask some painful questions, and you may not always like the answers you'll get, but it'll save you a lot of heartbreak later.

DON'T wait too long to meet your SO in person, and after that, if at all possible, try not to let too much time lapse between visits. The former is so you can move on to deciding where the relationship is going to go (if anywhere), and it's far better off to find out sooner than later, as stated above. The latter is to keep what will sometimes be unbearable loneliness at bay. Even a long weekend every other month or so can help, and unless your SO is working in a research camp in Australia and you're in Nova Scotia, no distance is so great that you can't manage at least a twice-yearly visit, even if it's at a halfway point. There are good airfare and other travel deals to be found, and with planning and compromise it can be done. Even prisoners can have visitors.

DON'T maintain an LDR with a prisoner. They usually only want money.

DO understand that there will be an ending to an LDR, and it will come quickly. Either one or both of you will end up moving to be closer, and you will then just maintain a "normal" relationship (though everybody's idea of "normal" is different), or...you won't, and the relationship will eventually dwindle down to nothing. Also understand that, once again, you and your SO have to both be aware and agree upon where the relationship is going to go. If you're searching the classifieds in his local newspaper while he's adding new and sexier pictures to his ad on OKCupid, there is a grave communication lapse somewhere, and it must be dealt with immediately. Other than in situations where you or your SO is in the military or in prison (and again, I can't emphasize enough that dating someone in prison, or while you're in prison yourself, is really not a good idea), an LDR really shouldn't extend past a year or so without some conceivable end in sight, whether that end involves planning your lives together or saying a painful but necessary goodbye. I recently found and browsed through a book recounting personal experiences with LDRs, including a couple who's maintained one for several years, with no intent on either's behalf of moving. I just don't see how this is possible. You know, unless you're some kind of emotional masochist.

DON'T attempt to maintain an LDR if you're under the age of 18. This is the big leagues, kids, and some level of emotional maturity is required to get through it. Many adults lack this maturity, as do even more teenagers. Really, at that age you shouldn't be committing yourself to someone romantically anyway, let alone someone who lives at least several hundred miles away from you.

DO be considerate of your SO's time, especially if you're in different time zones. It may feel like time stops whenever you're talking with your true love, but it doesn't, and while you may be ready and raring to go for another two or three hours of conversation at 9 p.m., it's getting well past bedtime for him or her. Alternatively, you should not feel like you have to stay up extra late every night waiting for the opportunity to touch base with your sweetheart. Oh sure, you'll want to, I'm just saying you're not required to, and your SO shouldn't make you feel as if you are. If you're the type of person who has trouble sleeping at night and is comforted by a voice on the phone, find a local friend, don't rouse your SO from slumber when he or she has to be up for work in three hours. LDRs are not for the selfish, and showing a consistent lack of consideration for your SO's time and needs, and vice versa, may give one pause to think that a successful long-term relationship is not in the cards.

DO learn to recognize "red flags". If something seems fishy to you about your SO or the situation itself, go with your instinct. This especially holds true if you and your SO have yet to meet in person, which is why I also suggest not waiting more than two months or so, if at all possible, before doing so. If your SO is hedging on meeting you "outside the box," so to speak, it could just be nervousness, self-consciousness about his/her appearance, or, hey, he/she could be getting red flags from you. This is all understandable, and again, with that vital communication, it can be worked through. On the other hand, he/she could already be involved in a relationship closer to home. He/she could only be interested in you for the ego boost he/she gets from knowing how you feel about him/her. He/she could be maintaining a number of LDRs, with no intent of any of them going anywhere. In the worst cases, he/she could be completely deceitful of who he/she is or even what he/she looks like. One of the sad aspects of the internet is many users' failure to acknowledge that, despite not really "knowing" them, they are still interacting with real people whose trust and emotions should not be toyed with cavalierly.
Some "red flags" that either I've personally experienced or have been noted by friends include...
--Giving only a cell phone number as a contact. Yeah, I know, this is pushing it in the day and age where some people don't bother with landlines anymore, but I gotta tell you, I have a friend with a knack for choosing less than suitable mates, and every one of them who only gave her a cell phone number did so because they were already living with someone, and of course didn't want to be called at home.
--Not giving any indication that he/she has told anyone about your existence. This is fairly self-explanatory. I'm not saying you or your SO should be making huge, gloppy public declarations of your love for each other (actually, that's a little tacky anyway), but if you've met someone, and you make each other happy, LDR or not you'll want to mention it to at least a few people who care about you and will enjoy your good news. If it becomes apparent that your SO is keeping your relationship a secret, find out why. Just chalking it up to being a "private person" isn't a valid enough reason. I'm a private person, my current SO is a very private person, but we quietly began discussing each other with our respective families and friends once we became a formal couple. Is someone not supposed to know about it? Find out who and why, and if this individual (or individuals) will remain an issue in your relationship in the long run. Is he/she embarrassed about being in an LDR? Sorry, kids, don't count on either scenario leading to a successful outcome.
--After a certain period of time, he/she still dodges any major discussions on where the relationship is going. This, sadly, happens sometimes once the initial first meeting takes place. The fact that in many people's eyes that makes the relationship officially "real" may cause some to panic and start wanting to back off without hurting his/her SO's feelings (this, of course, is impossible). Or, alternatively, he/she may be willing to discuss the next step, but shows no willingness to assist in taking that step. You may want to be the one to move anyway, but it doesn't hurt to ask your SO how willing he/she would be to move where you are instead. If he/she is absolutely adamant about not moving, or even changing his/her lifestyle to accommodate you, it may be an indicator of trouble ahead. Never be made to feel as if the responsibility for keeping the relationship on track is entirely on your shoulders, and never make your SO feel that way. You both chose to get into an LDR, it takes equal effort to maintain it and take it to the next level, if there is to be a next level. As in any relationship, it's about compromise, not control.
--Anything else that just seems fishy or off-kilter to you. A lot of it can and will be paranoia on your part, but a lot of it might not be either. If it walks like a duck and quacks like a duck and all that...

DON'T be embarrassed. LDRs are becoming more and more commonplace, thanks to the internet. Granted, successful LDRs are less common, but they exist as well. If the relationship ends, don't minimize it for the sake of others, your pain will be real, and it will deserve to be acknowledged. If it's happily resolved with the two of you living in domestic bliss, its chances of long-term success are certainly no less than a relationship that began in a bar or a bookstore. If anything, the chances are better, because by now you should have learned to communicate more clearly and constructively than the average couple, and you've already weathered an extended separation. Not that you'll want to go through it again any time soon, but you get the idea.

That being said...

DON'T expect everyone to understand or take it seriously. This seems to be a generational issue, as in, people your parents' age and older are more apt to minimize, if not discount entirely, the validity of your LDR. This especially holds true if said LDR began by meeting through the internet. There is a not as large as it used to be but still very vocal faction of people who believe either a.) finding romance on the internet is for the desperately hopeless individual who is incapable of making conversation with people in "real" life or b.) the internet is populated almost entirely by sexual deviants and serial killers. While this may be true in some cases, most of the time the internet is just a useful tool for people who are too busy with work, school, being a single parent or otherwise to be out on the scene. And yes, a lot of them are just shy too, but that doesn't make them a loser, or socially maladjusted, or whatever. The chances of running into a wannabe Jame Gumb are probably just as good on the subway as on a Lord of the Rings bulletin board. And really, where you and your SO met is incidental, if you're in a happy, fulfilling relationship, what difference does it make?

DO understand that an LDR is not for everyone. You have to be strong of both heart and will to make it survive. There may be nights when you will cry yourself to sleep. You will learn to both love and loathe the sight of your local airport. You will need to be certain that your SO is worth the time and effort necessary to maintain an LDR, and more importantly, if you're making it worth his/her effort as well. This is something a lot of us don't stop to think. In a successful LDR, the benefits far outweigh the hazards. After my first disastrous attempt at one, I swore I'd never get involved in such a thing ever again. Taking another chance turned out to be one of the best things I've ever done. As of this past July 13th, my own long distance relationship evolved into just a normal relationship, where we get to see each other every day, and it's been terrific so far. Be willing, be open, be smart, and just understand what you're getting into. Love has a way of making a difficult situation not so hard to bear.