Hi Av123, If she wants to join them, I say 'go, join them!'.
If she has an Anxiety disorder, it's possible she will have it on and off her whole life, or lurking in the background. (Disclaimer: It's possible she also just has a teen angst/puberty- type problem that she'll grow out of and never experience again, too - I'm not a doctor and don't know your daughter)
Either way, the more she can learn to live with the anxiety, the more she will get out of life. Anxiety can lead to hiding in your house and being too afraid to try anything. If she can learn to face it and live with it, even a little bit, she'll have a much more enjoyable teenage-hood.
I've had Anxiety since I was a teenager and sometimes it's crippling, but mostly it's not. I am (in some ways) thankful that (back in the Dark Ages before we diagnosed such things) I had a mother who pushed me into everything because I learnt that - it doesn't matter how frightened you are, you've got to give things a go. People tell me I'm brave and adventurous - no, I'm usually terrified but I refuse to let that stop me having a life.
Don't get me wrong, I'm not suggesting she can just override Anxiety and ignore it, not at all. I am suggesting that as she has said she'd like to go, that you both make the most of that little crack in the wall and let her take the risk of experiencing the camp. Talk to her before she goes about some safety strategies in case she gets anxious while she's away. But she may just have a good time - and that's worth the risk.
You ask if it will make things worse for her socially? I think it would be the opposite. Kids at that age are adaptable, it won't take the rest of them long for them to cope with 'so-and-so joined the camp half way through' and she'll be able to share in a few of the camp memories and stories once they're back at school.
Just my thoughts.
A mother's job is an almost impossible one - on the one hand you need to protect her, and on the other you need to encourage her to fly. Good on you for trying to do both.
