Luke i think to address the question one must first ask the question....who cares? But anyways on with the show. She realistically probably broke her own bong, piss can cause rust. For all we know shes "squirted" a few too many times on it and in it, and while she was taking a break from the marijuana smoking, and switching to cocaine, the rust probably built up on the bong to the point where it eventually cracked and broke. Thats the most probable explanation, at least with regards to that part of your story.