I know a lot of worriers, including my wife. I believe it all comes down to two things: control and perfection. Things you can't control make you worried, and you have this idealized version of what the outcome is supposed to be.

If there were any real answers that could be given, we wouldn't have people in the world who worry anymore. The truth is that what helps is different for everyone. I personally loathe self-help books, but I found that reading literature has had a significant impact on how I view living/life. Just keep an open mind and try a few things. Maybe what helps you is going to a sweat lodge twice a year, who knows?