I have had anxiety since I was in my early 20's I am now 64 and I am on Prozac and klonopin for about almost 20 yrs. I think that her having an out like she does is good it makes you have less anxiety knowing you can leave. The problem is she is too hard on herself. We are our worst enemies. It is hard to tell a young person, but since I went thru it my whole life I say I can look back and see how hard I was on myself for being so fearful. I could not help how I felt. It is hard to not have your mind build up all those feelings.I also have a daughter 27yrs old who has had anxiety and panic attacks too. She is so fearful she will never drive. All we can do for our children is too be there for them and be supportive and get them the help they needed. All I can say is I look back and say in the end it does not even matter lyrics from a Linkin Park song. Kind of like don't sweat the small stuff it really in the end is all small stuff. All we need at the time we are going thru this stuff is the support of people that are dealing with what we are.

I was played in bands for many years and also suffered from severe anxiety. At times it would get so bad that I would literally freeze and not be able to play. The only advice I can offer is to let her know that she is doing a great job and should never expect perfection in any situation. As musicians, when we overthink how we are playing, it stunts our abilities. She has to clear her mind of all the clutter and play by feeling it instead of thinking about it.

it's important to remember that while you are having the most severe of all anxiety attacks, you remain in control of your body.

Tell her to go on stage or just lip synch.

Tell everyone else to completely ignore her when she fails to get on stage. Make it an emotional non-event with no beneficial psychological outcome to her of attention or petting or poor you-ing. Leave it alone to be its own thing.

She's probably getting massively positively reinforced every time she fails, or does the mea culpa about failing. She has to swallow her own mea culpa. That's a consequence of her actions, not her anxiety. How she feels about what she does or does not do is a piece of the decision to act that belongs to it, and which she needs to carry on her own.

If she can, she might look into Propranalol. This is a medication used by performers and even presidents. It's a well proven, inexpensive beta blocker that regulates heart rate so your heart won't race which is usually the first thing that triggers a panic attack. Plus, no effect on behavior - it won't make her zone out or feel tranquilized. Just a low dose 45 minutes before going on - works great. Ask her dr if it might be a good fit for her.