Thoughts and the Truth

We've established that thoughts are incredibly powerful and that we have a high level of choice in how we manage thoughts once they pop into our brains.  Some thoughts can be very real, powerful, and seemingly valid to us without actually being true; consider an anorexic's belief that he/she is overweight.  How can we know the difference between thoughts that are very real for us and thoughts that are actually true?  And what do we do with untrue, unhelpful thoughts that continue to seem real?  Cinthia encourages us to take our thoughts to God and ask Him to test them against His own.  She also presents several practical exercises to help us manage unhelpful thoughts on a day-to-day basis.