my best friend moving out of state, please help T.T?

My best friend who's a girl is moving to a different state because almost everyone at her school makes fun of her,

saying things like she's fugly and they always harass her and hit her too

but she's not ugly, she's probably the most prettiest girl ive seen in my life and shes so sweet and nice, and they're just jealous of that

now she's moving because she couldn't take it anymore and i won't see her for the rest of my life probably and i love her more than just friends, so much more, ive known her for a very long time now and its really making me depressed

i need to say something to convince her to stay here, she's already booked her flight, and i need to tell her in a way not telling her that i love her, please someone help