Winston and Julia are both seeking freedom from the IngSoc society. They both feel trapped and want to express their individuality. They are both rebels, in other words.
However, while Winston's priorities are heartfelt, Julia's are not. She is practical, more so than Winston who often asks rashly, but she does not have deep seated convictions. She plays along with society by belonging to the Anti-Sex League, even though she doesn't believe in it. She also betrays Winston quickly when put into danger. Winston tries to maintain his convictions and rebellion, although his tragedy is an inability to stand up against the force of the new society.