Here is my short answer from Chunyi teachings, "where the mind goes the qi will follow".
Now for the rambling

. You can't destroy or eliminate negative thoughts. You are best to show them love. Regard them as fearful and ignorant children which should be loved and allowed to grow strong by experience and example. You should then give them the examples of strong mature thoughts.
More directly, think positive. Notice negative thoughts and choose to fill yourself with positive ones. Don't feed the weeds, just the grass and your lawn will be weed free.
Why do I keep wanting to talk in analogies? grrrrrr.
You are perfection.
Iam2
