i think As long as there is bitcoin users it  won't die ever, but if majority of the members are loosing confidence and not having an interest nor enjoying the features of bitcoin, well that's the sign bitcoin will down the price until the until comes nobody using bitcoin anymore and you are right when internet dies then bitcoin will be die but it really impossible and internet would be never die and bitcoin is depend on internet and there a lot of users of bitcoin and more people adopting bitcoin....