So would a more appropriate field name than tblFamilies be tblPeople?
Why have ID_Church_Info field in tblAddresses? I sorta get why LNSort field is in tblAddresses but think it is probably not necessary. And HomePhone is there in case there is a land line for that address, as rare as that may be now.
Instead of associating POBox with physical address, might have fields for Mailing and Physical addresses in tblFamilies then POBox and Physical address would be separate records in tblAddresses.
If you want to prevent an address record without associated family records, I expect need code behind main form to check for existence of related family records when main form closes and if none found, remove address record.