Winston, in the last paragraph of the book cries "Two ginscented tears trickled down the sides of his nose" as he realizes he loves Big Brother. He is sitting in the Chestnut Tree Cafe, and his long struggle against the state, he thinks, is over. He sees Big Brother's smile and berates himself for "misunderstanding" Big Brother for so long.
From the foreshadowing, which I will discuss in a minute, we expect Winston will be rearrested and executed.
The scene which foreshadows this is one Winston witnesses much earlier, before his arrest, in the Chestnut Tree Cafe. He sees three men who had rebelled against the Party. The focus is on Rutherford, once a brilliant cartoonist and now a broken man. Winston observes all three men, saying that:
There was no one at any of the tables nearest to them. It was not wise even to be seen in the neighbourhood of such people. They were sitting in silence before glasses of the gin flavoured with cloves which was the speciality of the cafe.
This exactly foreshadows Winston's fate because at the end of the novel he is sitting apart at the same cafe drinking clove-flavored gin and watching the telescreen, just as they are. We learn the three were all rearrested and executed, which is how we can expect that same fate to befall Winston. Rutherford, like Winston, is a broken man:
He seemed to be breaking up before one’s eyes, like a mountain crumbling.
The warning is that rebelling against the Party leads to death, so we should resist totalitarianism and the propaganda that enables it before it is too late.