It reveals for the first time that the former football star gave her a letter to open if he died while fighting overseas. The letter went untouched until he was killed by friendly-fire in Afghanistan in 2004.
Part of the letter read, "It's difficult to summarize 10 years together, my love for you, my hopes for your future, and pretend to be dead all at the same time."
Tillman quit the NFL to join the military following the September 11 attacks. His widow is now remarried and works full-time with her foundation, providing support and education for veterans and their spouses.