In my case I was the developer and I had worked two months past our decision to transfer the company to him, the non-technical founder. When I asked him (probably somewhat aggressively) to give me a few days off to get started after New Year's day he hired another developer. He went silent and hid this from me for three weeks until I found out from the client why nothing was a priority any more.
Eventually that new developer contacted me to ask about the details of my past business relationship with the guy. He was having the same problems with him that I had.
How do I describe the guy in retrospect?
I think he drank a lot and shot his mouth off about being a CEO kickin' back collecting the cheques too much. I did all the fucking work and he collected.
Even though we had been communicating about the issue in my case he took this as a sign to move on. I'm actually pretty glad he did. I was ashamed to let the client be stuck with him and all of his failures but sometimes that's the price you have to pay to keep your sanity when things go bad.
In the time since this has happened I have done a lot of awesome technical projects and he still has a broken webpage with nothing but errors on the front page.
It is hard to find a new developer. I strongly advise you to get introspective for awhile and figure out what you did to piss him off. After you've given him a bit of time to cool down.
Meeting in person or on the phone certainly helps too. Emotional data is lost in emails - best to avoid until you've patched things up.