Helena Bonham Carter said that her character was afraid of Harry because she couldn't understand how a young boy was capable of overpowering Lord Voldemort.
' It's pretty clear in the book, and implied in the movie, that Bellatrix gets "mad" after Harry's second Crucio, but she doesn't start to "panic" or get "scared", till she finds out about the prophecy being broken, and Voldemort shows up.
But the one thing she's afraid of, is the Dark Lord Voldemort himself. She is entirely in his control; a slave to him, and that's why she fears him. Voldemort and Bellatrix have a child in the Cursed Child, and here you can see their relationship relating to that of the Joker and Harley Quinn.
For example, despite being furious with Bellatrix Lestrange for her murder of his godfather in 1996, Harry Potter was only able to cause her a brief moment of pain with the Cruciatus Curse because he used it out of "righteous anger", though he was still able to knock her off of her feet with it.
This is precisely one of the reasons why Bellatrix was so engaging. She seemed to have a sick obsession with Voldemort that went so far beyond romantic desire. She was also very clearly scared of him and his remarkable magical abilities.
Harry tried to use this spell himself. The first time was against Bellatrix after she had killed Sirius. His attempt was unsuccessful because, as Bellatrix mockingly explained: 'You need to really want to cause pain – to enjoy it – righteous anger won't hurt me for long…'
His reaction to Bella's death was akin to his reaction at the loss of the Cup, which was when he realised that his own immortality was jeopardised amidst war and his own death could have been near.
Killing Her Own Cousin Bellatrix was responsible for killing Harry's best father figure, Sirius Black. She ruthlessly killed her cousin during the battle at The Department of Mysteries. She didn't show any guilt after she'd committed the crime either, laughing with glee about what she'd done.
The darkest of the Dark Arts, Harry Potter unforgivable curses are the Cruciatus Curse, the Imperius Curse, and the Killing Curse. Although the curses are highly illegal, Harry using Unforgivable Curses happened, but he uses them once he was thrust into the Second Wizarding War.
After being on the run from a bunch of Snatchers, the gang were taken to Malfoy Manor, where Bellatrix proceeded to torture Hermione using the Cruciatus Curse. It was a testament to Hermione's toughness that she was able to walk away without lasting damage.
5 Bellatrix Lestrange: The Cruciatus Curse.
Harry makes use of two of the Unforgivable Curses in the books. Dueling with Bellatrix Lestrange, he attempts the Cruciatus curse, with limited results; Bellatrix says that he has to really hate someone to make the Unforgivable Curses work properly, righteous indignation isn't enough.
Bellatrix had a fanatic obsession with the Dark Lord although she was clearly fearful of his magical abilities and absolute power over his forces. She's almost as sadistic and homicidal as Lord Voldemort, with a psychotic personality.
Draco's refusal to reveal Harry's identity to Bellatrix was not because he liked him. It was because he believed that Harry was the only chance they had at defeating Voldemort. At first, Draco admired and revered Voldemort until he threatened his family's safety.
Bellatrix Lestrange Killed her own cousin, Sirius Black: She killed Sirius (who was her cousin) during the battle at the Department of Mysteries. She was remorseless and was cackling in glee after she had murdered Sirius.
As much as Bellatrix loves Lord Voldemort, she equally hates Harry Potter, considering him the greatest threat to Voldemort and his plans. She will do anything to assist the Dark Lord's desire to defeat Harry.
Though Harry encountered many opportunities that deemed Avada Kedavra necessary, it remains as one of the Unforgivable Curses Harry Potter never cast. For one, he viewed the spell as an immoral practice commonly used by users of the Dark Arts.
There is likely a good reason that the Sectumsempra is not an unforgivable curse. It's mostly because Sectumsempra is Snape's personal curse that he created. It is not a widely known or used spell, and it is one that he kept secret — which means it can't be added to the list since no one really knows about it.
Voldemort intentionally made six Horcruxes, but when he used Avada Kedavra on Harry, he unintentionally created a seventh Horcrux. Instead of dying, Lily's love for Harry created a counter 'curse' known as Sacrificial Protection and saved Harry.
The answer is that Sirius wanted to deflect attention from the real Secret-Keeper. He probably hoped Voldemort would go after him so he could steer attention away from Pettigrew.
Harry would no longer have a pure soul. If he had killed Bella and then was possessed by Voldemort, V. would be successful at that. Regardless it would totally destroy the story.
If you've read Harry Potter and the Order of the Phoenix or seen the movie, you already know that it was Bellatrix Lestrange who defeated Sirius Black.
Bellatrix Lestrange
"What will happen to your children when I've killed you? When Mummy's gone the same way as Freddie?"
Draco Malfoy's mother Narcissa was cold, cunning and devoted to the Dark Lord. But she was also a mother, which meant she was willing to risk everything to make sure her son was safe. When Harry survived Voldemort's Killing Curse for the second time, Narcissa pretended he was dead so she could get to Draco.
He did not love anyone, and did not care to be loved. He felt nothing for his family, and only wanted his friends in school to rally around him because he wanted to hold power over them. Bellatrix Lestrange was obviously in love with him and worshiped him, but he only cared for her servitude, not her.