See that last quip there shows that she knows she is entirely full of shit.

She knows none of her advice is actually useful.

She doesn't care.

She just wants to always feel superior to you.

Same with bro in law.

'That'd be nepotism' means 'that'd be nepotism that I personally might not benefit from.

... here, I have the glasses from They Live, you can have them, but you're not gonna like what you see.

They know they're full of shit, they're complete hypocrites. Otherwise the advice they give would... you know, generally work. They don't care that they are complete hypocrites.

They have the mentality of scammers and con artists; a massively oversized ego that must continually be fed with I am awesome and everyone else is a sucker.

They do not actually care about you or your wellbeing. They care about feeling like a success.

If I were you, I'd cut them out of your life; all they're good for is wasting your time and causing you sanity damage.