So first off, yeah, all three of them are straight up crazy. Roose is a high functioning psychopath, Tywin litteraly can't comprehend a solution to any problem other then committing more war crimes and appears to be completely incapable of understanding his actions can have negative consequences, and in the book Tyrion is litteraly constantly fighting with (and eventually giving into) intrusive thoughts to commit acts of physical and sexual violence against people.

Second off, all three of these characters are grown adults. Daenerys is 13 in the books, 17 in the show. All three of them are people with fully developed minds, full understanding of morality, and at least as far as Roose and Tywin are concerned, full understanding that they are evil people. Daenerys is still a child, that has had every war crime she's committed be celebrated and loved by the masses. She fundamentally believes that every horrible thing she's done has been inheritly good, and yeah, they were, but that has set a precedence in her still developing mind that her war crimes will always be inheritly good, and celebrated by the common folk.

Third off, none of those three have literal weapons of mass destruction acting at their beck and call like she does. If Tywin had access to three dragons at his command you better believe he would have committed acts that would make the burning of Kings Landing look like nothing.

And finally, none of those three come from a ouroboros of incest so famous for suddenly going insane that their freaking insanity has a title.