These days, I eat a primarily vegan diet... probably somewhere in the vicinity of 90-95%. But I'm not perfect on that score, and there have always been exceptions to my rules.
I've never worried much about beeswax or honey, for instance (although I might start, considering the plight of the American honeybee these days). I don't freak out if I think there might be fish sauce in my Thai food. If a friend cooks a meal for me that she thinks is meat and dairy free, I'll eat it without reading her labels (even if I find out later that there's some animal-derived ingredient lurking in the recesses).
And about once a year, the boy and I make a trip up to some farms north of Des Moines, where we sample goat cheese and ice cream made from happy cows and goats we've personally petted in their barns. This year, I brought home some chevre. I think we'll indulge tonight while we watch Masterpiece Theatre on PBS.
While I would understand if anyone disagreed with my exceptions, I don't feel bad about them. I'm not on a crusade to be sinless. I'm just doing my best to reduce the amount of harm I inflict on the planet and its inhabitants. Having a little goat cheese once a year doesn't nullify the choices I've made the other 364 days.