That's why the block button exists.

Tell 'em...shut the fuck up, normie, bitches!

that's why the logic button exists

Then avoid facebook, social media is one of the worst things if you have an opinion on something. I'd say avoid it, I find social media sites like that silly, and if they got to my that much, I'd just stop going on them. Since there is no reason keep hurting yourself by going back on there. 

Or blocking them like others have said could be an idea too. Or just ignoring them, since people are always going to disagree with you, especially religion.

Block them and add your family from here buddy.