Long Distance Relationships

As I am about to enter to an almost a year-long long distance relationship, I have to ask, "What is it about long distance relationships that make them so different than being in a relationship where you both live in the same city".

I have yet to find the answer, but I hope to illustrate some points on the observations that I have made of people that I know who are in long distance relationships, including myself...

More thoughts to come.