How to deal with completely delusional yet totally normal people

It's really an absurd world that we live in. Many people around me, friends, family, colleagues etc, all believe in the most amazing things - God written books, God Man combos, Young Earth - you name it, someone I know well (not crazy) believes in it.

So how to deal with this?

1. Just say, c'est la vie and don't even think about it.
   
2. Acknowledge that most people are cognitively immature and incredibly biased and there's nothing you can do about it.
   
3. Go with some wacky 'epistemic justification' philosophy and say that all these people are being perfectly rational.
   
4. Rant and rave about how incredibly stupid and delusional everybody is.
5. Just like 2, except with a POMO stance acknowledging that you too are cognitively immature and incredibly biased and there's nothing you can do about it either.
6. This is about feelings, not reason. Feelings just are.

Any other suggestions?