Claudia was more cruel to Louis in the seance because he was supposed to save her and he didn’t.
And I think this is a dynamic a lot of people with bad parents can relate to—or rather, more likely, people who have one Bad Parent and one Good/Less-Bad Parent.
The objectively worse parent’s awfulness you get numb to. They are static and almost one dimensional to you, where their bad behavior gets internalized as something inevitable and fundamental to who they are. They are inherently bad, they are not capable of loving you (or loving you in a way that matters), they are unchangeable because if they COULD be changed, your other parent or you should’ve been able to change them, right?
They can be many other things, you can have complicated feelings about them (love them even!!) and their bad behavior, but their badness is a core part of how you relate to them. It’s a permanent caveat, a bright red asterisk.
Your Good Parent (or Less Bad Parent or Almost Aways Good but Sometimes… Parent) is met with a lot more love. Because… obviously.
But the issue is sometimes you resent them more than the Bad Parent because you aren’t numb to them. You love them but they are also the person who invited the bad parent (bad step parent, bad boyfriend who comes over to the house, etc) into your life. The person who took care of you is now failing to protect you. They love you enough to do their best but don’t care enough to shield you (or themselves) from the bad person.
It’s irrational, often victim blaming, but it becomes, “I get why Bad Parent is bad, I don’t forgive it, but I accept it as an unmoveable truth. Why is Good Parent failing me? This parent is meant to protect me and they aren’t. Why is their love not enough? Why am I not enough for them to move away from this bad person?”
Abusive family dynamics are more complicated than that but I think a lot of people can relate to the idea of expecting bad behavior from certain people but being much more personally betrayed when a trusted person fails them, even if the failure is less severe than what the Bad Person did.
Claudia learned early on Lestat was fucking awful. He was her Bad Parent. And she had his throat slit and coffin dumped into the garbage over it. She punished him and she got away from him. (Which is also a huge part of this—she got to punish Lestat, she got to one up him already, he knew exactly how she felt already.)
Louis was supposed to be her protector, the one to run away with her. He stayed when she ran. And then when she was forced to come back, he fucked up their escape because he loved their abuser too much, and only then did he run away.
And… he ran straight to Armand, who also abused her along with his coven. And he killed her.
And when Louis’ guilt became too much, when the truth became clear to him, the first thing he did was fly back to Lestat. For closure!! OVER HER!!!
She’s alone in hell and Louis’ path of getting closure over her murder was reuniting with a man who played a part in separating her forever from Madeleine.
And this is a more intimate betrayal than what Lestat did to her because that wasn’t meant to be the terms of their relationship. Louis was supposed to do right by her. He was supposed to protect her.
And it hurts so much worse when even the good parent can’t do right by you. When their goodness and their love isn’t enough.
So, yeah, sometimes you resent the person who was better to you, more like you, than the person who actively hurt you, hurt you both even.
Abuse kinda fucks you up like that.