Yeah, it's complicated. If I were starving on an island and could dive for lobster, I'd feel no guilt, or at least the absolute minimum guilt.
But throwing a live lobster that I bought into a boiling pot doesn't seem so natural to me. I realize I'm not actually helping to save these creatures, but it makes me feel better about myself to abstain. And it's very healthy for my energy levels :)
Not sure if this comment would help you think better, Lobsters were not suffering much.
This is how I did it:
http://www.saveur.com/content/ingredient-guide-lobster