(I took scenes from the book btw)
Harry had been having meetings with Dumbledore and he was learning more about Voldemort's past and he learned that Voldemort had split his soul 7 times and had created 7 horcruxes. What Harry didn't know is that Draco had been given the impossible task to kill Dumbledore.
Narcissa Malfoy (Draco's mother) was worried about her son so she made the unbreakable vow with Severus Snape and made him promise to help Draco with his task and fulfill the task if Draco couldn't complete it.
Harry had just gotten back from the cave with Dumbledore and Dumbledore had told Harry to go get Snape.
Meanwhile Draco let some fellow death-eaters in the school which included Bellatrix Lestrange and a vicious werewolf named Greyback.
Harry made Ginny, Ron and Hermione take the rest of his liquidluck to ensure their safety in the battle and he made them round up Dumbledore's army members to help them in the battle.
Hermione and Luna were keeping guard outside Snape's office but he got past them.
Draco also got past Neville, Ron and Ginny by using instant darkness powder.
Harry watched as Draco went up to the astronomy tower and disarmed Dumbledore.
Harry heard Dumbledore talking Draco down by saying that he wasn't a killer and that he was just a boy and that he could help him turn to the good side.
Draco said "I don't want your help, I have to do this, I have to kill you, or he's going to kill me and my entire family".
Draco continued to point his wand at Dumbledore but as he looked at the man that he was supposed to kill he couldn't do it so he lowered his wand but Bellatrix and the other death eaters came up so Draco pointed his wand at Dumbledore again.
Bellatrix whispered in her nephew's ear and said "Do it, just kill him".
Draco kept pointing his wand but at last he lowered his wand.
Snape then came up and pointed his wand at Dumbledore and said "Avada Kedavra".
Dumbledore fell off the astronomy tower and Harry watched as the man that had always been there for him was killed.
Snape then dragged Draco and the other death eaters out of Hogwarts but Harry caught up with them and shot multiple jexes at Snape who had blocked them all.
Snape and Harry then started to duel but Snape of course got the upper hand and then he said "I'm the half-blood prince, don't use my own curses on me".
Snape then got the rest of death-eaters and they all disapparated.
In july of that year Dumbledore's funeral was held and everyone in the school was absolutely distraught by the news of Dumbledore's death. Harry was crying over Dumbledore's body and Ginny stood up and went to go comfort her boyfriend. Ron was comforting Hermione and stroking her hair as Hermione cried on his shoulder.
Later after the funeral, as people were starting to leave Harry went up to Ginny and said "Ginny listen, I can't be involved with you anymore we've got to stop seeing each other, we can't be together".
Ginny said "It's for some stupid noble reason isn't it?".
Harry continued on and said "It's been like... like something out of someone else's life these past few weeks with you but I can't, we can't ... I have things to do alone now".
Ginny didn't cry but she simply looked at the boy that she had loved for most of her life.
Ginny told Harry about how Hermione had told her to relax around him and that maybe then he would take interest in her.
Harry said "Smart girl that Hermione, if I only I asked you sooner, we could have had months, years even".
Ginny said with a laugh "But you've been too busy saving the wizarding world, I'm not surprised I knew you wouldn't be truly happy unless you were hunting Voldemort, maybe that's why I like you so much".
Harry couldn't bear to hear these words so he stood up and turned his back on her.
Ginny was heartbroken, the thing that had made her happier than anything the world, had turned his back on her just a few weeks after they had started dating. Sure she understood why he did it but that didn't make it hurt anyless.
Harry then told his friends that he wasn't coming back to Hogwarts the next year and that he had to find Voldemort's horcruxes and destroy them. Ron and Hermione both agreed to join Harry on his journey.
Harry knew that breaking up with Ginny was the right thing to do, he had done it for her safety, he didn't want anything bad to happen to her she meant everything to him, she was the light that drove him.
But Harry knew that he had an important mission in front of him, he had to save Ginny and the rest of the wizarding world from Voldemort, he wasn't called the Chosen one for nothing.
