First: Beauty is the hero. Beast is the villain. You are not required to agree with me on that, but it is how I see the story. Whenever someone writes a Beauty and the Beast remake where Beast is not at least the antagonist, I'm confused.
Starting from that point, here is a summary of Beauty and the Beast:
It's the hero's journey. There are problematic aspects in the romance that I've glossed over, but I do not recall a time when I thought Beauty and the Beast was a love story any more than I thought of Snow White and Rose Red or Rumpelstiltskin as a love story. They include a marriage, but that's not the point. It's a fairy tale. Because Beauty is brave and loyal and strong, she gets a happy ending. That does not guarantee me the same. But it means it's possible, even when it looks bad.The hero's living parent gets accidentally wrapped up in a deal with the villain of the story. The only way for the hero's parent to survive this deal is for the hero to face the villain. The hero faces the villain in the villain's own realm. The hero goes through a variety of trials, which are created by the villain's own meanness. The hero endures these trials, and slowly learns things she did not know before.
Beauty's marriage to the Beast is about as relevant as Gaston. Both of them serve to show that the antagonist has changed, that mean people don't necessarily remain mean. I understand the issue with this, the implication that a person should stay with an abusive partner--but would it really be any better if Beauty had killed him, as is the more common fate? If I am alone with an abusive partner, I am probably not going to be able to kill them. Beauty shows the virtue of endurance, of being able to pick herself back up again. She is not staying with the Beast because she thinks they have a perfect love (at first); she is staying with him to save her father.
I was the little girl who didn't always know how to tell people when she was being hurt, and often didn't trust the people who were supposed to protect me even if I did. Beauty did not tell me, "Make them into better people!" Beauty did not say, "Someone will save you; just you wait." Beauty did not explain, "If you are strong, you should be able to fight them on your own."
Beauty told me, "Some people will hurt you. Some are Beasts, who may become better. Some are Gastons, who will not. Either way, you can endure them. Do what you can. Maybe you can't win, but you, little one, you are strong. You can survive this."