If she's anything like my mother she doesn't actually -want- help, or any help they can give will never be up to her standards so she shoos them out of the room and does it herself anyway.
his job is a therapist.
If I had to wager a guess, he works with mostly lost causes so he sees a lot of shit that would just cause people to lose faith in humanity.
Apparently it's not uncommon to call your SO's parents Mother and Father as a sign of both respect and your dedication to their child. I'm not sure about the "-in-law" part.
Does Haru see the glamour looks like a person version or does he drop down to skeleton to make a point here? You know, I've never seen an undead maintain the grudge against humanity to motivate them by working in something like therapy or the service industry before, but it really seems a great match.