pull the boot up around the edges, and see if anything is noticeably broken. (it takes 2 seconds).
if that is intact, get under the the car (on jack stands or ramps) an look above the k frame. I would venture to guess the broken spot is the transmission mount pivot. But have someone move the linkage around and see what it is doing.
that leads to my next scenario. it is a solid linkage, so once your dog bone wears, your shifter gets sloppy.