Even though Fleur seemed to complain about Hogwarts every other sentence on her first trip there, she did a remarkable job of adapting to the new environment. She became extremely social and was able to achieve the level of popularity she probably held during her first six years at Beauxbatons. Even after the Tri-Wizard Tournament was over, she still returned to England, first to work, then to marry, and then to live out the rest of her life.
In life itself, Fleur showed she can adapt to just about anything. She came to England a shallow, teenage girl, a person she adopted most likely because it was what got her ahead at Beauxbatons. But as the series moved on, she adapted to become a soldier in the Second War, a caretaker for the injured, and then a wife and a mother of three. When reading GOF, Fleur was the last person I believed would ever settle into a domestic life, but look at her.
Fleur seems like the type of person who can mold herself to fit into any environment.
I'm not quite sure how much of this is just due to her veela blood, but Fleur has a very charming personality to her. She is able to get both teachers and boys completely under her thumb. Although she seems to have no ability to use this towards girls, I doubt this counts. Teenage girls all seem to secretly hate one another, even when they have no reason to.
For better or worse, Fleur is honest to a fault. While at the Tri-Wizard Tournament, she never kept her opinions to herself about how she believed Hogwarts was so inefficient to the Beauxbatons palace. This did not earn her a lot of friends in this way, but at least no one could accuse her of being two-faced.
Even after she was done with school, she kept her honest opinionated fully alive and well, even though the Weasley's really didn't care for that nature. But later, it came to serve in her favor, for her in-laws learned that Fleur's words could always be taken at face value, no matter what it was she said.
Even though her honest nature did not always serve her with certain people, it made her someone who could always be trusted with her words.
When Fleur is first introduced in the series, she is thought of as a very selfish person, and loyal would be one of the last words people would think to describe her. But once she chooses to stand by Bill, even after he is attacked by a werewolf and he loses his good looks, Fleur still chooses to become his wife.
During the war, she stands loyal to the cause of fighting Voldemort, even when it makes her wedding a terrifying affair and she and her husband are forced to go into hiding. Still, she remains loyal to the Order and tends to their injured, doing whatever she can to help the cause in her own way. A selfish person would not make sacrifices in such a way.
The last word that could ever be used to describe Fleur would be naive. She has been all around the world, and is one who knows the true nature of all human beings. She does not shy away from these truths, and can almost be described as having a hardened strength to her.