They did not discuss the possibility of getting married, as it was too remote to be worth thinking about.
No imaginable committee would ever sanction such a marriage even if Katharine, Winston's wife, could somehow have been got rid of. It was hopeless even as a daydream.
Winston and Julia both rebel against the party, but they are completely different in their reasoning, inspiration, and motives.
Winston rebels in hope that future generation will be free of the party and be able to live in something like the Golden ages or the times he remembers from before the party took over, or at least in a time where they are free to think what they like and are not denied the privilege of the truth.
Julia, being younger has no memories of a time before the party and therefore can't imagine a time without the party in control. She rebels not for the future generations, like Winston, she rebels more for the sake of just rebelling.
She is against the party and what it stands for but she never really says her reasoning. The only time Julia questions the party's teachings when they somehow touch upon her own life. Julia also accepts lots of what the party says simply because she didn't seem to care much of the difference between a lie and the truth.
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