Poison
Honestly I agree it's easiest to say I'm fine when you don't want to speak. I do it more often then I would like to believe. If you ask me how I am "I'm fine" or "good" is what I will say. To me those two just mean I'm still hear aren't I? Honestly what do people expect when they ask someone how are you, do you expect a long conversation about their terrible life, no you just want a simple less than five syllable answer. There is no point in elaborating because if you do then someone might know too much. Even with our friends we lie because who's to say they won't turn away from you, you don't want them having all your poisons. My friends in my opinion already know too much. So yeah that's why I just say, "I'm fine" because I'd rather not tell you my life story.