Depersonalization is a strange disorder in which the sufferer feels that they are living in a dream world; it is the feeling of watching oneself act, while having no control over a situation. It can be considered desirable, such as in the use of recreational drugs, but it usually refers to the severe form found in anxiety and, in the most intense cases, panic attacks. Often a person who has experienced depersonalization claims that life “feels like a movie” or things seem unreal or hazy. Also a recognition of self breaks down (hence the name). Depersonalization can result in very high anxiety levels, which further increases these perceptions – a snowball effect. One way to describe the physical manifestation of the feeling is to compare it to a film technique called the vertigo shot or dolly zoom. In this technique, the subject of the picture stays fixed within the shot while the surrounding background is pulled away, providing a sense of vertigo or detachment. 

Source:
http://listverse.com/2009/07/21/10-more-incredibly-bizarre-mental-disorders/

Thi is a horrible feeling. I was diagnosed with panic disorder at one time. It has since been changed to Generalized Anxiety Disorder and Major Depressive Disorder. Medication helps! Take it if you need. There's no reason to be miserable.