I wonder if the husband has some form of ED and is projecting his anxieties/obsessions onto Scarlett’s Mom? Does he police his own body as well? If he doesn’t, he’s got a misguided sense of entitlement perhaps bordering on narcissism; if he does, then maybe he needs to eat some more food, as well!
I wonder if he is also having trouble adapting to the idea of fatherhood? Maybe wanting your earlier body is a kind of nostalgia for life pre-baby? But, of course, harping on one’s wife over a pretty insignificant weight gain isn’t the way to deal with it.
Objectively, 137# at your height is not “fat.” Most people would describe that size as “normal.”