I'm glad to hear that. And the costume shop you went to sounds so cool. I'm glad you found a great costume for Shane!
I'm sorry Katie. I actually do think that's normal though. I mean we feel how we feel and cannot change that. kwim? It doesn't mean you wish them ill will or anything. And it's really not even them you dislike, but their behavior. Two separate things. You can love a child, but hate the way they act or things they do.
I don't think that at 7 and 9 they are set in their ways. That's still young. They can be taught to act differently. HOWEVER it would take time and consistency from ALL the adults in their lives. It's not something you alone can do in the short amount of time you spend with them.
I hope who ever is their main caregiver or parent works with them to change their behavior. Even if that means some sort of counseling or other intervention. The violent comment especially worries me. At this age, they can still change. If their behavior is allowed to continue it will get out of hand. And as a teen, they'd be much harder to control and could become dangerous to themselves and/or others.
What does their mom do about them?? It's really her responsibility to take care of this. And hopefully she will. For their sake and those around them.
In the meantime, if they are causing you to be this upset, you need to limit your time with them. Or at least take a break. It's not good for you and you are under enough stresses of your own.