[shamino]

This is what I learned from Dale Carnegie, which seems to help. Imagine the very worst thing that can possibly happen, and try to imagine your life with that reality. See that it's not actually so bad. Then, do everything you can to prevent that from actually happening. Taking action, instead of thinking about it, helps. Also, distract yourself with positive relationships and exercise.

And a quote which is a little lighthearted - Michel de Montaigne said: “My life has been filled with terrible misfortune; most of which never happened"

[neverartful]

Not sure if the part you suggested is from the book or not, but OP might want to read Dale Carnegie's How to Stop Worrying and Start Living book.