there's a notable difference between people who have experienced the dead and who haven't.

I get Sansa's side of it and how its a balancing act, and she's hardened quite a bit from going through so much, and doesn't have much faith in other people. but like you i get uncomfortable with her always publicly disrespecting Jon. I think she does trust and respect him but at the same time there's still that part of her who looks down on him.