Bloody hell. I'm sorry to hear that - from the looks of it you had something really special going on. Of course, I'm glad that you did not compromise your vision (ugh, that sounds cheesy), but I can't help thinking that you must feel like the mother in Salomon's judgement. Don't. Be glad that while this particular instance did not reach fruitition, you've hammered out a lot of what an eventual implementation would be like. Learn from that.
What I'm trying to say is that this is not a blank "Where do I go from here?" I was worried that Unity's cancellation would be the end of having a small developer go for a different game (from which everone benefits), but with thought I can't help being slightly optimistic. You were doing Unity at the end of the Gamecube lifecycle. Now, you have an entirely new generation of hardware to play with. And the market that made Lionhead want to publish Unity, is not going to go away. Perhabs some thought must be made on what exactly Llamasoft can realistically develop in the future, but this is not the end of gaming as we know it.
Have a NCoT. Go outside and give the beasties some scritchies (especially Ewenity). Take a long break (even from us, if you need it). But for goat's sake don't retire!
(Oh, and there's always the VLM!)