It seems to me that John's discussion of wills and insurance isn't perceived by Elly as that sensible, caring thing it really is. He, despite making chauvinistic and pompous comments here and there, such as deciding to permit her something that's already a given like her remarrying after he goes, he really is looking out for her best interests because he wants what's best for her. Too bad he doesn't acknowledge he just reminded her of her worst fear. She already suspects that he might be sizing up those pretty receptionists and assistants as a potential replacement; his discussing the event of her death adds fuel to that fire. You see, if he were to die, she'd be destroyed financially and emotionally. Her fears tell her he'd be doing fine without her. She'd be on the mantelpiece in her urn while in a year's time tops another woman would be living her life, cleaning her house and raising her kids. Eventually, she'd be nothing more than a faded memory. Given her fear of being irrelevant, of her life not having an impact, that's a horrible thing to remind her of. Poor John. He can do the right thing and still be thought of as a jerk.