Certainly, neither Winston, the "common man" of Orwell's futuristic society, or Julia, Winston's Juliet,--"Winston woke with the word "Shakespeare" on his lips"--are content in the controlling, bellicose society in which they live. However, they are very different from one another, if not contrary.
1. While Winston is aging, Julia is vibrant and young and not as grave as Winston.
Winston is thirity-nine years old, suffering a malaise of the spirit:
It was as though some huge force were pressing down upon you – something that penetrated inside your skull, battering against your brain, frightening you out of your beliefs, persuading you, almost, to deny the evidence of your senses. I
He suffers from a varicos ulcer on his right ankle, the symptoms of which lessen when he is in love; on the other hand Julia is pretty, dark-haired, very physical, and energetic, enjoying the moment. She tells Winston,
"I've been at school too, dear. Sex talks once a month for the over-sixteens. And in the Youth Movement. They rub it into you for years. I dare say it works in a lot of cases. But of course you can never tell; people are such hypocrites.
Unlike Winston she is not intellectual, but she is vibrant while Winston seems weary. She throws off the usual caution that she exerted in previous lovemakings for Winston; however, he is not able to be as spontaneous as she, often lying with her and thinking of political issues.
2. Winston is more cerebral and reflective as well as cautious whereas Julia is spontaneous and delights in the physical.
In order to record his musings, Winston purchases a diary, a forbidden object, and records his thoughts and feelings as he secretly vents his hatred for Big Brother and the oppressive society in which he lives. In his diary he writes such things as "Thoughtcrime does not entail death: thoughtcrime IS death." When he puts away the diary, Winston reminisces about his mother and a time when there was still "privacy, love, and friendship."
At the Two-Minute Hate Session he is immediately distrustful of Julia,
But yesterday, ...she had sat immediately behind him when there was no apparent need to do so. Quite likely her real object had been to listen to him and make sure whether he was shouting loudly enough.
But, Julia simply wanted to be near him as she passes Winston a note that reads,"I love you."
When Winston and Julia engage in lovemaking, for him it is political in nature, a rebellion against the government by establishing a loyalty for another person; for Julia it is simply physical and emotional pleasure.
3. Winston is fatalistic; Julia is content to live in the moment.
Winston has recurring recollections of what his childhood was like and he muses on the love his mother had for him--perhaps, a Freudian wish to return to the the security and affection in his past. Constantly, he seeks something to give his life meaning, and this is why he turns to rebellion even though he knows he will be caught, but it is the only way to find truth, that which makes life viable and real.
He does not hide his diary, figuring it will be found anyway; he knows that he and Julia will be caught, but he continues his actions, longing to join the Brotherhood and reading Goldstein's Manifesto. Because he believes he will be caught, Winston takes risk that endanger Julia as well. On the other hand, Julia just enjoys the warmth of being with Winston and their making love for itself; she is apathetic to the political thought of the Party. Nevertheless her short sexual escapades wear away at the Party's control over her.