I just found some cute quotes!! if you dint like them you dont have to use them just putting them out there!!
"No matter what happens, I'll always be with you. Forever."
Pocahontas
With this you could say some thing like.........No matter what happens, I'll always be with you. Forever. with that then you could ask her to go to the dance with you!!
(Not my favorite)
"Don't you understand [What ever her name is]? You mean more to me than anything in this whole world!"
Peter Pan
You could say.......Don't you understand [name]? You mean more to me than anything in this whole world! So will you please go to the dance with me.
(Or something along those lines)
All of this has happened before, and it will all happen again.
Peter Pan
If you have taken her to a dance before you could say something to the effect of......All of this has happened before, and it will all happen again. If you will go the the dance with me!!
The last one is my favorite!! Might have more later!!