From a psychological perspective, Downton Abbey demonstrates how times may change, but certain human challenges remain the same. The season finale includes the typical drama and heartbreak, but what is most interesting about this episode is its thematic exploration of the human struggle with transitions, identity and self-esteem.
As the season opens, Mary jokes with Matthew that it is no longer 1850 and so she is determined to enjoy and embrace her pregnancy rather than hide herself away. While clearly excited about impending motherhood, Mary's frustration about the physical and social limitations of pregnancy lead her to question her identity. When Matthew implores her to give Lady Edith's new suitor a chance, stating "just be as nice as you are" Mary responds:
"You think me nice, but nobody else does. What makes you so sure I am?"
Matthew assures his Mary that she is, indeed, nice, replying:
"Because I've seen you naked and held you in my arms and I know the real you!"
Mary projects a vision of absolute confidence, and yet she is not able to answer an exceptionally basic question. Her lack of clarity about whether or not she is, indeed, nice demonstrates an identity struggle with the tension between how she is experiencing herself, and how is imagines others see her. This is a psychological struggle quite common to adjusting to motherhood and to so many other stages of human development.
Tom Branson's identity struggle is much more obvious and painful to witness. Isobel Crawley characterizes Tom's transforming but fragile identity while they dine together one evening. They are together because the rest of the family is away on a holiday and neither Isobel or Tom are invited:
"Tom... you've managed a delicate transition superbly... but don't be too eager to please. You have a new identity and I don't mean because you're not a chauffeur anymore. You are the agent of this estate and as the agent you have a perfect right to talk to anyone who works under you. Anyone you please. You have a position now and you're entitled to use it."
The new house maid, Edna, takes a fascination to Tom's transition from the downstairs to the upstairs, and attempts to both embarrass and seduce him as she mocks his wardrobe:
"When you first came back as Lady Sybil's husband, you refused to dress the part, but you do now."
A shaken, somewhat humiliated Tom protests:
"I was tired of talking about my clothes every time I came downstairs. I'm still the same man inside."
And an unconvinced Edna then asks:
"Are you ashamed of who you are or of who you were? Is that why you won't eat your dinner with us?"
Tom may be Edna's boss, but Edna seems to have all of the power as she waltzes with confidence out of the room.