Well, she was probably severely dehydrated. As coke has caffeine in it, you do not get the hydration your body needs.
And of course, all the chemicals in that stuff are nasty!
I usually have coke when I eat street food, if you have seen what coke does to a piece of meat, you know what ever you eat will be completely annihilated by coke...no chance of getting sick.
Has so far worked perfect for me! :)

Otherwise I don't touch sodas.