Life feeds on life feeds on life feeds on life feeds on...
You're not special. Humans are not special or separate from nature in any way. It's impossible to live without killing vast numbers of other organisms. The rodents killed by combine harvesters are more intelligent than cows and chickens.
There's no health benefit to a vegan diet vs a vegetarian or mostly vegetarian diet. The only "benefit" is ideological smugness.
Animal "rights" groups probably do more overall harm than good, by alienating the general public and reinforcing the idea that conservationists are all emotionally-driven smug vegan hippies. They deter people from helping out with sane environmental causes due to fear of association. PETA soaks up donations that would otherwise be going to shelters, research, and real conservation projects, and spends them all on troll-tier advertising, keeping their wiki page free of criticism, and insulin for their president, while not actually doing anything to help animals or the environment.