Now there's 40,000 denominations, eh??? When you going to provide some proof for this claim???
He won't, because there isn't any proof to that claim. In fact, there are 21 major traditions of protestantism, and 16 of Roman Catholicism, meaning the Roman Catholic Church is nearly as "fractured" as some try to make protestantism to be.
It's simply a slanderous/pejorative statement meant to incite and inflame. Forgive, show him correction, then forget. If he continues with his ignorance it is between him and God.