I'm new here, but I've been a vegetarian since college (about 14 years now) and a proper vegan for nearly a year.

I fell into veganism almost accidentally -- the amount of dairy I was consuming was decreasing naturally over time without any active effort on my part to eliminate it. One day realized how little of it I had in my diet already, and just decided to go all the way and get rid of it entirely. Now I'm never going back!  :)