Albert Camus and Jean Paul Sartre were proponents of nihilism.
According to Eric Metaxas, both became Christians before their deaths.
Well, existentialism. It's only slightly different than nihilism, but there is a difference.
Nihilists believe nothing has meaning, while existentialists believe nothing has inherent meaning. Instead, they believe we just invent meanings to assign to things, rather than that they have any meaning independent of what a human gives them. So an existentialist might believe his relationship with his wife has meaning, not because marriage is sacred, but because he has decided that it will have meaning for his own reasons.