Apparently [on Tumblr] you can't reblog yourself. WHY ARE ALL THESE LIMITATIONS ON WEB SERVICES?!
Someday I'll make my own social network. It will be a service you can install on your own website and your friends can join. But! it's a protocol that can talk to other sites that host that service. Think like email. Yahoo, Gmail, Hotmail, and even Schools and Organizations all have their own version of email, but they can all talk to each other! how great would that be?
So like in my idea, people can use tumblr if they want to host their social media. Or they could use missing e. Or they could host it on their own website (like I would use halloweenbagsearly.com).
Anyway, this is how things should work. The only reason services don't do this is because they want to be able to sell you ads and have control over your information.