Snape's fourteenth memory: Snape and [Dumbledore] stand in the grounds, arguing about why Dumbledore is giving Harry information that Snape does not have, and with Snape demanding to know what is going on. Dumbledore agrees to speak with him in his office that evening instead.
Snape's fifteenth memory: [Dumbledore] reveals to Snape that Harry himself is a [Horcrux], and that he will have to give up his own life in order for Voldemort to be killed. Dumbledore asks Snape to tell Harry this when the time is right - when Voldemort fears for the safety of Nagini - and leaves Snape angry that after all he has done to save Harry, Dumbledore concealed from him all along that it was only for his eventual death. Snape also reveals his [Patronus]: a doe, the same as Lily's.
Snape's sixteenth memory: Snape plots with [Dumbledore]'s portrait the way that the Order of the Phoenix will move Harry from the [Dursleys]' house, keeping him safe while still informing Voldemort of their plans.
Snape's eighteenth memory: Flying through the air with the Death Eaters, Snape tries to curse a Death Eater who is going after Lupin and George, but accidentally hits George instead, cursing off his ear.
Snape's ninteenth memory: Snape sits in Sirius's bedroom, reading a letter from Lily, and sticks the page of her letter with her signature in his robes, along with the half of the photograph that she is in.
Snape's nineteenth memory: Snape plots with [Dumbledore]'s portrait again, and when he hears from Phineas Nigellus that Harry and Hermione are camping in the [Forest of Dean], he thinks of a way to deliver [Gryffindor's sword] to them.
Knowing, finally, that he must sacrifice himself, Harry sits in [Dumbledore]'s office, thinking about all that has led him to this point. Finally he stands and begins to walk, determined to meet Voldemort in the [Forbidden Forest].
On his way to the [Forbidden Forest], Harry runs into Neville, dutifully caring for those who are hurt or dead. He stops to tell Neville that Nagini needs to be killed, then under his [Invisibility Cloak] continues on through the grounds, past Ginny, to the forest and to Voldemort.
Once in the forest a realization his Harry and he pulls out the [Snitch] left to him by [Dumbledore]. It indeed opens, and as he turns the [Resurrection Stone] over in his hand, Harry realizes that shadows of his parents, and of Sirius and Lupin, surround him. They walk with him, comforting him, until he finds Voldemort's clearing; and upon announcing his arrival, he drops the stone, and his family disappears.