Just as I was starting to feel better he sent me an email
So apparently reasons for breaking up were more technical than emotional. And that just says that there were no emotions at all from his side. Sweet.
I've responded that technical difficulties can be overcome, but lack of effort and willingness even to mention them to your partner is something else.

I'm not even feeling sad now. Definitely not happy, just numb. And I like it. I wish I could stay numb...