I first became a vegetarian when I was 12 years old. So I've been a vegetarian for over 10 years. My original reasoning was just because I loved animals too much to eat them. Plus I just wanted to do something different from everyone else. It was just a rather random decision for which I later came up with justifications and reasons. I don't eat anything that once had a heartbeat, but I do eat dairy and eggs.
Part of the reason I stick to a vegetarian diet is that I'm very uncomfortable with slaughtering practices, and the idea of raising animals just so we can eat them is absurd to me (not to mention a self-defeating waste of resources).
Another of my reasons still has to do with emotion/sympathy for the animals. I don't want to eat them because I like them too much as companions, and I do have sympathy for them. I am indeed concerned for the well-being of all animals around me, and it does concern me when an animal is unnecessarily killed for food. I don't care to downplay the influence of emotions and sympathy on my vegetarianism, although it is still only a part of the reason. It just bugs me that everyone else tends to devalue the effect of emotions on our actions, but we have, after all, evolved to become emotional, not just rational, beings and it has served us well in many ways. I just prefer to maintain an even balance between reason
and emotion...
I also no longer like the taste, smell, or appearance of most meat. If I were to suddenly stop being vegetarian tomorrow, I would be able to begin eating chicken/turkey again, but the look, taste, and smell of beef or pork is rather disgusting to me now. It baffles me now how I could have ever eaten that putrid crap. *need a green puke icon here* Due to my changes in taste, I can't even feel comfortable eating tofu hot dogs or certain types of veggie burgers because they resemble the taste of the "real thing" too much (I only like the Original Gardenburger because it's not supposed to taste like meat, and it doesn't).
I want to stop eating dairy food, just because I think it's a little strange to rely on another species of animal to provide something that humyns can produce for themselves if they really wanted to (haha). Plus it's another one of those "not really necessary" parts of the diet, once you hit a certain age anyway. I have tried numerous,
numerous times to become vegan, but it never works. Having grown up in Dairy Country somewhere in the Midwest, dairy food has just become my staple food, so it's really difficult trying to phase it out. Not only that, but I'm a lazy cook, which means that if it doesn't come in a box or a can, then it doesn't belong in my kitchen. Having said that, it's almost impossible to find completely vegan food that comes prepackaged in a box or a can. So I fall back to my old habits all the time (plus I just can't live without pizza, and the vegan variety is just way too expensive for me). As for eggs...blah, I don't really have an opinion on them. It bugs me when egg-laying chickens live in bad conditions, of course, but now they have free-range/organic eggs and stuff. But I don't really consume eggs that much anyway, so it's irrelevant to me.
But it's largely my objection to the treatment of animals and the deprivation of their free lives that causes me to be vegetarian. If I were shipwrecked on an island, and my sustenance depended on the eating of some sort of animal, I would of course attempt to hunt them and eat them. I have few moral objections to eating animals in a situation where it's necessary.
I certainly don't push my beliefs or practices on others though. If I did, I don't think my meat-eating partner would still be living with me.