I believe you need to take a minute and try to see this from your daughter's point of view (not saying she is right). She resents your wife because in her eyes, your wife prevented you from getting back together with her mother. And she resents your young children because they're living the life, she feels your wife robbed her of. She is using her wedding as a way to punish them as retribution for the pain she has unjustly attributed to them causing. I think that because she formed those opinions as a child, she still has a childish view of the situation and is approaching this entire situation as a child.

I think you need to have an in-person conversation with her. And I would start it by saying it pains you every day that she was a child of divorce (acknowledging her feelings). Tell her you're proud of her and the adult woman she has become. Then explain, as an adult she needs to realize making your wife/kids feel small and unloved will not change her upbringing. It only serves to make her look petty on her wedding day.

If she is firm that they cannot come, I think you need to go to the wedding and walk her down the aisle. And when you leave the church (temple, etc.) you should go home and not to the reception. You should be there as she swears to love this man forever because you will love your daughter forever. But you are under no obligation to celebrate a day where she has set out to hurt you. Good luck to you, there is no winner here.