This is awful @thgdd55
This is a time you need to really help your daughter understand some stuff about how men try to control women through taking away their confidence and humiliating them. By hiding inside she is letting them win and take away her self esteem and her living a happy life. She mustn't let them do this to her.
Firstly, attractiveness and societal ideas of this are used to control women and the aim is often to make women hide away, feel self-conscious, feel ashamed for whatever reason. It's simple bullying. Like a lot of bullying it's often just insecure pathetic people trying to humiliate others outside their group in order to curry favour inside their group. There is nothing that your daughter need feel ashamed of. Nothing that should make her hide away. These are just bog standard bullies making themselves feel bonded inside a group by going for someone outside their group. It means nothing about her. There is nothing objective here at all. Women must try to resist attempts to bully them out of the public sphere whether that be in politics, life, positions of power, or simply taking up space in public and in our public spaces. Look at some of the amazing women who people are attempting to bully out of public life. Maybe this might make her feel less alone. If they can do it...
Second, not that it matters a jot, but this lowlife found her attractive. So this horrible ceremony is something more about a general misogyny and nothing personal not even from this lowlife. Don't let them win. Stand up against this generalised misogyny but be aware of the potential nastiness of groups and particularly male groups.
If it's any help you can tell her about me who was once horribly abused for being fat in public, by a group of women, and the one who was the most abusive was twice the size of me. Whilst it was horrible to experience, it was so strange and obvious I was able to stand back and think what is going on here? Sometimes it's people's self-hatred and view of themselves that can create bullying nastiness, not their view of you. It's nothing to do with you and you have to try and get that distance and not take any of it on board. I'm attractive and that incident doesn't change that. I'm sure your daughter is too although of course her experience is so much worse than mine, but hopefully she can also shake it off eventually and be her own supporter.
Third, there are some good old feminist tomes like The Beauty Myth. I don't know if there's a moden equivalent. This is quite a useful set of ideas to look at in terms of ideas of "beauty" are created, capitalised and utilised in order to control women. Ideas of beauty are different in different eras and can be wildly varying. What unites is the way they are used to make people feel less than whether to be controlled by another person (sometimes by a family, or sometimes an abusive individual) or controlled by markets that want to get people to buy lots of unnecessary stuff. Take your own power and decide to stand up to that as well.
Lastly, give her a massive great hug and tell her she's loved and is beautiful and is a great person who is needed in this horrible world to get out there and be one of those who are decent and not let the lowlives take up all the room. This is horrible for her to go through. Being loved and supported is so imporant.
To add, if your family witnessed the toast why on earth didn't any of them march over and give them a piece of your mind?