This is too sad. I have heard some say that it's not the number of years you have, but what you get out of the years that you have. I hope that is the case here. She died way too young.
As I seem to recall, Jessi got her start in the television world as an intern on the Mythbusters. If I am thinking of the same person, they gave her some screen time on the show, and she seemed to be a natural working in front of the camera.