My family are not divided at all on religious matters. We're just not of a religious bent in any way whatsoever. We do have differing opinions on the EU and brexit, plus some have reservations regarding same-sex marriage. It would seem to be a typical microcosm of many UK families.
We don't fall out about any of this. We've learned not to become obsessive in our desires to swing other family members over to our point of view. If we do discuss any controversial points, we keep our voices low and calm and back off immediately if anyone shows discomfort.