Coming of Age
So, this movie can be looked at as a man growing out of his youth and becoming an adult, but the film starts with Shaun stuck at a point everyone gets stuck at: what kind of adult does he want to be? Everyone he comes across can come be a symbolic representation of various phases of maturity.
- Ed is the true diehard Manchild, with no aspirations to improve his life or be more verbose with his words, yet he finds nothing wrong with doing the same things he's done for possibly his whole life.
- Liz represents someone who is trying to become mature, broadening her horizons, but as shown at the end when she kept the cigarettes, she shows it's not too bad to fall back on old habits.
- David... Well, David makes himself look like he's matured, but his obsession with Liz and pathological hatred of Shaun shows that just because you look mature, doesn't mean you are mature.
- Barbara and Philip are an older couple who have found their rhythm in life, and are okay with helping others, Barbara with her love for Shaun, and Philip trying to help Shaun find his own motivation, even at the end realizing he went about it too hard for him to appreciate what he was doing.
- Yvonne can be something of a flipped mirror of Shaun, going through the same thing he is, buying for herself, even commenting that it might just be "a bit grown up of her," and when she bumps into Shaun during the Zed attack, her party is a direct mirror of Shaun's own party, so it shows that while Shaun is going through this maturity, he's not alone.
- Pete is someone whose found his maturity at the expense of his happiness, and thus a Foil to Ed; he's hard working, maintains the house, gives out chores and the like. But he has nothing else to himself: he has no other friends or even a girlfriend to speak of, no family he mentions; he's someone whose given up everything for his job, AKA his maturity.
So thus we reach the Bookends of the movie, where Shaun is walking like a sleep deprived zombie. At the beginning, he was just going to play video games with Ed before being reminded he has work, while at the end, he's sitting on the couch of a much needed redecorated flat to talk to Liz about any plans for the day, but still takes time to have two sugars with his tea and spending time with the now Zombified Ed. He's found his rhythm, making his character development is complete.
