Arnie’s character doesn’t know his own wife. He doesn’t know her hopes and dreams and he doesn’t notice her anymore It’s pretty clear they don’t have much of a sex life.
That scene is meant to be about how he finally sees her again. It starts out with him still being an asshole but it ends, or is intended to end, with him realising he’s been wrong.
But I agree it doesn’t really work. It’s too creepy a premise to work.