I don't know. There was no sudden realization other than "Ooooh. It's called being a FURRY." I've related animalistic qualities in myself since High School; people called me wolf (or Proto, if they knew about the character) all during school and after. It was just kind of who I was, how I thought; a lot of the characters I made were furries anyway, at least in early stories, and I still have a habit of attributing human qualities to any animal I write. I didn't intend for Loose Jaw to get a personality, but sure enough, once his genetics change in Fall he starts to become more aware of the self, as it were.
Long story short, I always had been, just discovered that's what it's called, and always will be.
And I've never been happier to find like-minded people. Everyone here was so accepting and encouraging and supportive. I love everyone on TFF. All my favorite fursons are here. I love you guys!