She can retract her statement however this will still be used in court. If she has not made a statement, she SHOULD NOT!
If she has, she should not attend court, if she is summonsed, she should turn up and say: Good morning to you and your colleagues. You will note that I have completed the requirements of my summons and I will now leave the building.
They cannot force her to give evidence. You should not under any circumstances admit to breaking the window. Without evidence or witnessess, the CPS will have to offer no evidence.
DO NOT BREAK YOUR BAIL CONDITIONS. THIS IN ITSELF IS AN IMPRISONABLE OFFENCE AND WILL ALWAYS BE PROSECUTED!