After watching this film

I get the impression that in spite of all her obvious weaknesses Mary was the only character worth the audience's sympathy, and moreover it looks to me like that was precisely Mike Leigh's intention.

The protagonist couple, with their smug sense of moral auctoritas, chronic hypocrisy and quasi-ritual gregariousness, feign empathy for the despondent but their private conversations, as well as their reactions to difficult situations (e.g. the Imelda Staunton character, as well as Mary's rudeness to Katie which warranted a harsh warning but certainly didn't deserve shunning) reveal them to be, and probably have been for a long time, complicit in a common cold, impatient and uncaring demeanor towards other people's problems.