I used to be really concerned with preserving all forms of life. When I turned 18 years old, I swore off meat and became vegetarian for two years, then vegan for two more. I attempted several times to convert to a raw foods only diet, at all costs avoiding animal products of any kind, including leather and fur. I distributed brochures defending animal rights and fastened a birdhouse to a tree in my backyard, though the birds seemed to prefer the trees over the house.
True story: One day I was wandering through a garden when I passed by an old white plastic bucket with a burgundy wasp floating on the surface of the clear water inside. It was still very much alive, though I guessed it would not be able to survive much longer on its own. I picked up a nearby twig and dipped it halfway into the water, pressing it against the body of the insect. It desperately clung to the twig with its six little legs. I felt very proud of myself at that moment for the positive results my ethical way of life had merited. As I basked in the glow of self righteousness, the wasp scrambled up the twig faster than I expected. It gripped my index finger and dug its stinger deep into my skin. Shocked, I dropped the twig immediately, flicked my wrist and the wasp fell to the ground unharmed. After all I had done for that ungrateful insect (I had saved its life, after all) it knew no better than to recognize me as a threat in its state of weakness, and to defend itself as instinct demanded. I learned a lot that day.