I have alot of experience in this area.I know how frustrating it is to have thoughts that seem to come out of nowhere and cause a multitude of feelings like fear, anxiety anger and frustration. Most psychologists and psychiatrists will call this obsessive compulsive disorder or obsessive thinking disorder.I hate to say this because natural alternatives are always the best route,but meds can help.Usually these thoughts are a product of subjecting yourself to highly stressful situations on a regular basis.One product that has helped me tremendously in this area is the centerpointe program,you may wanna look into it.My best advice for you would be to sit down and close your eyes and allow these thoughts to come into your mind and observe them with without any emotional attachment.If you feel an emotion come up ask yourself 'ala' Sedona Method "would I be willing to letgo of this feeling in order to feel better" and keep doing this until you feel a shift or lightness in the body. Also another program that has had a very beneficial impact is Think Right Now.Check out thy're website at thinkrightnow.com