I was 40 and already had a head of prematurely gray hair (I hide it well) when Dr. Testroet called with the crappy cancer news, but the following words from Jen Wilkin’s 27-year-old experience ring true inside of me. Once you hear a cancer diagnosis, you can’t unhear it. Even with successful treatment, it changes the way you number your days. I had been given an opportunity not many 27-year-olds could claim: the opportunity to count each of my days as precious. Any illusions I might have had that this life would last forever were effectively removed. I learned a…