You're taking all of this way too seriously.
It's just a company. Sure, it was one that you poured everything you had into, and I'm sure you associate a great deal of your self-identity with it, but it's still just a company.
Some context: I sold my first startup, which I co-founded with my wife, to a company about 3 years ago. We worked there for two years, and then they fired me. I had poured so much of myself into trying to make the product survive post-acquisition that when they showed me the door, I just sort of walked around in a daze, not realizing what I was supposed to do next. Then, gradually, I started to realize that there was a life for me after the startup, and one in which I could do better things than I could ever have working for the company that fired me.
Over time I came to realize that the product wasn't really that important. It was just something I was working on for awhile. If I wanted, I could go build a new version of the same product, or I could work on one of a hundred ideas that I have brewing. Once you realize that pretty much everything is ephemeral, you worry less about each individual step in your life and are able to focus more on the big picture. When it gets dark around you, it can seem like the world is much smaller than it actually is.
I think there's something appealing about having an "arc" of some sort to your life story. In reality, life isn't a play in three acts, and you get lots of chances to define and redefine yourself.
Just be honest, clear, and concise with the people around you. Take your share of the responsibility. Take some time to understand what happened, how you feel about it, and what you learned. Use that information to become better in the future.