Loyalty To An Extent
How far will you go to be loyal
Julia and Winston are loyal to each other until their lives were in jeopardy. At this point they became more worried about themselves than being loyal to the other person.
Quote One (Book Three, Chapter 5)
This relates because once Winston is faced with a terrible death he offers up Julia and is willing to let anything happen to her as long as he is left unharmed.
Quote Two (Book 3, Chapter 6)
This goes to show that you are willing to do anything to save yourself. Even if it is offering up something close to you or something that means a lot to you.