Q188: Do the witnesses have to sit outside court with the defendant?
Whilst it is possible that the accused will also be outside the court room, it does not follow that you have to sit in the same area. Many courts have large communal areas and will announce which case over a tannoy so that if you wish you can sit away from the accused. Alternatively, speak to the court usher and tell them where you are going to be.
At most courts there will also be the Witness Service/Victim Support who will be able to provide a separate room for you if you do not want to sit in the communal area. It is perfectly understandable that you would not want to sit outside the court with the accused in your case.
Alternatively you can contact the officer in the case who may be able to make some arrangements for you.