It's a natural human response to avoid pain. In fact, our nervous system is designed to keep us safe from pain, like when we pull our hand away from a hot element without even thinking or when we notice someone following us on a dark path and we automatically head for the busy street. These are helpful responses that happen so quickly in our brains that we don't even recall thinking about what to do, we just do it. When it comes to mental or emotional pain, our nervous sys