Do you run and hide, peering out from behind your floral curtains.
There is some suggestion about positive re-inforcement of the self, but if you think 20 thoughts, 19 of them positive and forced, when the single negative thought comes in, that is where the concentration goes.I think it is far better to accept and learn from the shadow self, to embrace rather than deflect.
There are times where you still have to remove yourself from negative situations, but most can be weathered, with a little mental fortitude.