It seems your 'friend' has the same view as most on here: that friendships are accessories to suit one's life, and one's life only. Nothing to do with you personally, your value as a person, all to do with what they want, when. In which case your friendship was not what you thought. Out of sight, out of mind? 
It can hurt very much to realise you were only an accessory to someone's life, especially if all evidence suggested otherwise. Perhaps she can't handle the distance - but that still shows she isn't committed to your friendship. As a pp said, sometimes a breakup with a friend can be worse, hurt more, than a romantic relationship coming to an end. But you're supposed to not be tiresome (needy, selfish, self-absorbed...) to have expected a friendship that was once very close to endure. It's apparently bad form to make a fuss - even privately on here - because that's embarrassing: being slowly dumped from a very close friendship isn't cowardly, it's 'how social interactions work'. People don't generally want evidence of their selfish choices, so showing your hurt, even privately, is hitting a nerve; hence the cavalier responses on your thread imo.
Bear in mind in future that it's considered wholly acceptable to pick up and drop people to suit one's tastes/their usefulness. I would consider keeping up with someone every year or so out of duty because they are dull to be a foul attitude but that's considered acceptable so you have to get used to it: it's not about respecting people for who they are but how useful they are to you.
I'm sorry you've been so hurt by this ex friend. Back off now and give yourself time to grieve. Keep 'friendships' light in future, bearing in mind you may well only be useful to them at a particular point, as someone to hang out with for a while, but no more. That's ok in general but very hurtful if it was genuinely a close friendship you reasonably expected would go the distance (literally) 