I've been vegetarian for 30 years now, and have drifted into a vegan diet without really trying, or consciously thinking that it was a vegan diet I had. The smells from meat and dairy really put me off putting them in my mouth, plus the industries themselves are off putting. It's difficult to avoid meat and dairy, with all the by-products etc, difficult to live an everyday life without rubbing shoulders with death and misery. Diet-wise it wasn't too difficult to stop eating meat and dairy once I had committed to the ethics of it all. I also started seeing meat as muscle, subcutaneous tissue and skin, for example looking at a slice of bacon. Ye it all tasted nice but felt very wrong, eating my fellow mammals. I don't preach about vegetarianism/veganism, but I do get a lot of stick when refusing to eat meat etc.