The sigh is the telltale sign of all husbands worn to a nub by years of criticism from a chatterbox harridan of a wife. Watch and see what happens the next time he opens his mouth. Wrong again!!! Bzzzttt. Just not worth the effort to divorce her but not quite to the blow your brains out stage, so he sits and sighs.
Far from it. She is very much in love with her husband...they have been married over 30 years. I have never heard her say anything nasty about him. I have heard him cut her in what he perceives to be a joking way. But she is a sensitive person.
She is affectionate and everyone loves her. But she has struggled with various things. Her husband had an affair years ago and she has suffered from some depression. She is now a regular church-goer (he does not attend) and that seems to be helping her somewhat. My take is that she wants her husband to connect more with her intellectually (offer ideas, for example, with the raising of their kids and provide spiritual leadership) and that is why she is a chatterbox.