People drift apart, it always happens... No matter who they are and how good a friend they are to you. You meet other people, they meet other people. But the people you meet don't like the people they meet, but you want to go and see the new people you've met. Stuff doesn't always work out the way you want it to.
I don't think you should tell her you don't want her to go, if I were you, I'd just go with her and see if you bond a bit
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