Jim, a marathon runner and young father with testicular cancer proudly told me "I've been in remission now for two years and just now am becoming less fearful." By this, he really meant that his life had filled up again with enough normal things and his medical appointments were sufficiently far apart that he wasn't constantly reminded of his disease.
That serpent is both clever and sinister. Its first tactic is to get you to believe there is nothing to be afraid of (denial). Then it adds false bravado. "I'm smart and the doctors are smart. I'm strong and determined and courageous: with sheer willpower I'm going to beat this thing." Denial and bravado are just cover-ups for panic and retreat, glaring signs that the big fear has already got you.
Rachel told me how pondering the unfairness of it all and all the dreams she had to abandon made her furious and that her anger got her nowhere. Expressing her feelings helped, but the more she did that the more exhausted and defeated she became. It was only when she let it all go that she could get the dragon off her back. Not until she accepted that fact that she would never know why could she move on with life,: make new dreams and regain the energy and composure she needed to take full treatment.