Winston Smith is at the Chestnut Tree Cafe, drinking Victory Gin and listening to the telescreens. At an announcement about the war with the Eurasian army, Winston feels a mixture of excitement and dread. He seems concerned about the outcome of today's battles. He writes in the dust on the table: 2 + 2 = 5.
Winston remembers a time in the recent past in which he saw Julia by accident. She seemed changed, thicker somehow. They both confessed to betraying each other. Winston did not feel that he was in danger in speaking with her; quite the contrary. Winston's life has changed; he no longer works at his former job, and no one seems to care much what he does. He has a vivid memory of his mother and sister and pushes it out of his mind, positive that it is false.
The telescreen announces victory at the front lines, and Winston is overjoyed to tears. In the end, he is happy to have won the struggle over himself; he loves Big Brother.
Totalitarianism has won over humanity; Winston is one of the masses now, putting his real self aside for the Party, for Big Brother. Still, he has ambiguous feelings and is haunted by memories of a former time, but he has effectively convinced himself that these feelings and memories are false.
The meeting with Julia resolves some unanswered questions: She did indeed betray Winston, in the same way that he betrayed her. She is becoming like the other women in the novel, sexless and undesirable, just as a woman of the Inner Party should be. When Winston and Julia meet, they repeat each other's phrases, just like Mr. Charrington did earlier in the story, a subtle device to show that they are truly indoctrinated. They are using the diction and the speech patterns of the Party.
Ultimately, Winston loves Big Brother, and will, presumably, spend the rest of his life loving him and waiting for the bullet in the back of his neck to set him free.