I'm in a long distance relationship (2000 miles) and while it's very difficult, it's not impossible.
- Assess your relationship. Make sure the relationship is *worth* the effort. It may sound like a frivolous question but honestly, it's something you have to address. If you're not 100% sure that this person is going to be in your life for a LONG time, at least long enough to make it worthwhile, then it might not justify the heartache.
- COMMUNICATE, COMMUNICATE, COMMUNICATE. The biggest pitfall of many long distance relationships is the failure of this very very important element. Try to call each other at least a few times a week. Every day is best. Put aside some time regularly to talk. Make sure you talk about EVERYTHING. Feelings, events in your life...even the most mundane ones. This is the best way to keep a healthy relationship without being toghether.
- Faithfulness. If you adhere to ANY common "rules" about fidelity (i.e. the "area code" rule) then it's over. End it now. Trust is by far one of the most sacred points of a relationship, and without that you have nothing. If you KNOW you're faithful and trust yourself, then it's that much easier to trust your partner.
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- Even though a long distance relationship is still a relationship, it by no means follows the normal rules of engagement that apply to what you'd consider a "normal" relationship. You have to learn to be very flexible. Don't nitpick or let the small things get to you; those are things you can work out when you're together. If you harp on small details like the tone of voice one uses, to other little habits, then all these little things will pile up and wreak havoc on both of you.
If you let yourself enjoy the relationship, and if you truly love the other person, you can make it work. Good luck to you!