In the 4.5 years since I stopped eating meat, my reasons for being vegetarian have evolved from my initial focus on health and preventing chronic disease. That is still important, but now I have other compelling reasons, environmental impact and social justice being at the top of the list.
Most people will not choose as I have and give up meat entirely, and that is fine. Rather, think about ways to eat less meat: reduce portion sizes, incorporate meatless meals every week, and encourage others to do the same.
Recent reading, including the book I mention here, provides evidence that animals (and meat) can be raised and consumed in ways that sustain the environment. If you do eat meat, try to find a local source. Take the time to talk to the cow/chicken/pig farmer and find out about his/her practices. Go visit the farm and see the animals. What do they feed the animals? How do they handle the manure?
For now, I am happy and healthy as a vegetarian. My diet includes eggs and a moderate amount of dairy. The eggs are from local free-range or pasture-raised hens. The milk and some of the cheese comes from an in-state dairy. Other cheese comes from smaller, local farmers.
Will I ever eat meat again? Maybe. But I will do so with some pretty high standards.