"Setbacks" are part of the process of healing.  Jerilyn Ross, President of the Anxiety Disorders Association of America, calls setbacks "a critical part of recovery."

A friend of mine who has completely recovered calls setbacks "growing pains."  

I believe that setbacks are a call to a deeper level of healing, and that they can actually signify a readiness to move forward.

In hindsight, the worst setback I experienced was one of the greatest blessings of my life.  It got me to change what I was doing.  It got me to start reaching out and opening up to new ways of healing.  It led me to the greatest period of healing and growth in my life.