i think it's okay to feel like that, it's always hard when a friend does better than you at something. please start putting these posts on some other thread (like confessions:http://www.cricketmagkids.com/chatterbox/downtoearth/node/457039) because like people have been saying it's pushing other, more used threads down. :)

okay so i've been putting off answering this because i'm just so jealous that she even had the chance to audition for Juiliard, let alone get in - regardless, some advice that maybe will be mildly useful hopefully? (also, i'm sorry i didn't say anything on your competition post, I meant to do that too. but i'm assuming it's okay not to since it's over now.)

if she has to move, i suggest writing letters with her. I write letters with a friend who moved, and I made it very clear that he doesn't have to write very often, but I enjoy writing to him, and I think he appreciates it, even though so far he's only written back once (probably not intentionally, he was busy because he moved and he also has ADHD - actually i have 2 pen pals and they both have ADHD, and I have ADHD, so we're like the ADHD pen pal gang XD not great for actually getting stuff written (or, in my case, not losing it and failing to ever get it to the mailbox) though XD). i sinecrely hope she doesn't make a bunch of friends there and drop you - maybe you could even tell her you're worried about it, and say that you really want to stay friends? Idk if that'd work? i'm not good at this stuff? but maybe? 

as for whether it's okay to think like this, you can't really control your thoughts or feelings, and everyone's going to think things that are bad sometimes - the important thing, I guess, is just to try not to let them influence things, so like, not being mean to your friend because of them (i'm not saying you're doing this). 

i'm sorry this is really useless but i'm posting it anyway XD 

oops - i pressed submit instead of preview - if it says anything weird i'm sorry XD

If she has to move and doesn't wish to write letters, then texting or Zoom calls or emails or something could work.
It's definitely okay to be sad/be jealous/have mixed emotions if other people are better than you at things. There are all these people who used to be awful at swimming compared to me, and then they're getting faster much faster than I am, and I dislike them for it even though they're perfectly nice people. However, I like to remind myself that there are people who were once faster than me who then have taken seasons off to play basketball or something and are now getting faster slower--you could do that yourself with violin? I don't know if that helps, but it may.