Don't you sweat it, Lypi! :)
Summer Camp sounds like an absolute blast!! I always wanted to go to one like that.
Of course she will still be your friend! If she decides not to be your friend, well, she wasn't that great of a friend then, was she??
Like you said, you can always keep in touch with her over the summer. Try calling instead of texting! It provides more of a human connection than texting.
If she does make more friends, you should be happy for her! And then what? You make new friends (or get to know her new friends)! Do't section yourself off to just one person :)
I hope this helps. Doubt it does. Anyways, I hope you have a TON of fun at Camp!! Woot woot! :D