Here's a thread that gives a little background on it: What is dissociation

I dissociate frequently. It is an anxiety reaction that dates back to my childhood abuse--a coping mechanism. If you can't physically flee a crisis, your mind can help you mentally/emotionally flee.

Everyone dissociates, but there is a difference between 'normal' dissociation like staring into spacing and thinking for a few moments and 'traumatic' dissociation where you feel separate from your body or are completely unresponsive.