I sometimes have the same “problem”. In fact, the most serious relationship I’ve ever been in was with a girl who lived half-way around the world. (We met whilst traveling; continued emailing/skyping; but it didn’t work out in the end; full story here).

I’ve found myself in little flings with other “geographic undesirables” as well. I think it has to do with the fact that you always imagine the best version of this person. You don’t get involved with their day-to-day flaws, so what’s left is the gorgeous funny intelligent person who would totally be The One if they weren’t so far away.