I was vegetarian for years. My reasons were simply that I do not like buying meats from the store that most likely came from a factory. Once I started getting meat from local farmers I changed. I do still struggle a bit with "should I eat something I'm not prepared to kill my self?" I suspect if I was hungry enough, or my family was I would be able to change my ways and slaughter my own food.
I agree that nature can be very cruel. However, most of us humans are used to an over abundance of food currently. It leaves us contemplating what mark we want to leave on this earth. What is best for the animals, what is best for the environment and what is best for our health. There is enough information out there for us to all form completely different idea's on what is a good and environmentally friendly diet and all be at least mostly correct.
Atilla-One of my daughters and myself both have celiac as well, so we feel for you on the restricted diet. On milk though-I find a lot of the nut milks work well in coffee. I personally don't like cow milk much though. In cream sauces or chowders I do like goats milk though, a little goes a long ways for a very rich sauce.