What can you do? He wants out. That's it.
It does come across as controlling, but when you are the one doing the dumping, you are in control of the situation. It is still a shock and probably will be for a while. And of course you have feelings for him. It's been a couple days?
What he is expecting of you is that you will chase after him, that you will text him, beg for him, and so on. It doesn't sound like you want to do that so you are already off to a good start. I don't see what more talking will accomplish. I'm sure you want your reasons and to be able to rationalize this, but what he gave you was reason enough. Good luck with any conversation. The pertinent question in my mind would be "how long have you felt this way?" There wasn't a fight involved, it's not like in the heat of the moment it was "that's it, it's over". He had to have been thinking about this for a while, and the fact that he was talking about all your future plans as little as a couple weeks ago is misleading and even dishonest. That's not fair to you.
Being a person with some emotional withdrawl problems myself, I doubt anything was solved the first time you guys broke up and he fell back into the routine and got comfortable again without any real change after you guys got back together. And what happens when it fails and nothing changes? It will fail again.
I wish I could say something to make you feel better or have a surefire suggestion to fix you guys. If he doesn't want to be bothered, don't. The best thing you can do for this is be indifferent to the whole thing. I'm sure he is going to be frustrated and feel alone when you have no response or any support for his decision. Take it one day at a time.
Waking up next to a beautiful girl,
Step outside and say hello to my beautiful world.