Therapist A is a counsellor with a psychodynamic approach with experience of working with adults and young people.
I am sorry that your daughter is suffering in this way. It is very difficult for you both as there seems to be no one clear reason why she experiences these symptoms. However ‘school phobia` or ‘school refusal`, as it is called by the professionals, is not unusual. The causes of this anxiety are very individual, but broadly speaking you need to think about what is going on at school and at home.

At school, is it possible that your daughter is being bullied or has friendship difficulties? Is there a chance that she is not doing as well as you or she would like? Has she started a new school recently? Perhaps rather that trying to get information from your daughter you need to talk to teachers and other people connected with her. Perhaps she finds it difficult to talk to you as you are feeling so concerned about her anxiety symptoms and refusal to go to school.

At home, are there or have there been any family difficulties that may have affected you daughter. You don’t say anything about other members of the family. You say that there are no problems at home but sometimes they are not obvious. It could be the case that your daughter is anxious about leaving you for some reason. Have there ever been any anxieties about being separated from you or the family before? Has the family lost anyone close? There are numerous possible causes, some more obvious than others and I wouldn’t like to draw any conclusions from your letter.

I think you need to find some good professional help. I assume that you live in France so this would most likely be accessed through your generalist. I think you need to explore what is happening to your daughter as a family with someone who is trained to understand young people and families in a psychodynamic way. This problem needs help. It won’t go away by itself.

Meanwhile there are some things that you can do to help. Keep life as normal as possible. Make sure that there is a containing structure to your daughter’s day. Try to stay calm yourself and reassure her of your love. She doesn’t feel safe except with you, so try to build her confidence in herself. Stop questioning your daughter but try to talk to her as much as possible about other things which interest you both. I do hope you manage to help your daughter with her school refusal. The sooner you get good help the better.
Therapist B is a Relate-trained counsellor with experience of working with relationship issues and is an experienced couples counsellor
I'm so sorry that your daughter is suffering like this, but it does sound as though she may be suffering from some form of bullying- either on the bus going in or at the school itself? It may also be that she is scared of telling you in any detail, as one of the consequences of bullying is being threatened if the victim tells a parent or anyone in authority at school.

There is a web site dealing with bullying, based in the U.K., but it has general useful advice & an email, helpline facility which might help your daughter to identify with others in similar situations & to realise that she isn't quite as isolated as she may feel. It does sound very sensible to talk to her Dr & hopefully make sure that her general health has been checked out, but again if nothing is helping calm her nerves then perhaps you could make an appointment to speak to her teacher/head. I guess it is still better to check all this with your daughter as she is grown up enough to feel she is being consulted. Otherwise it may be that your Dr knows of a family therapist who could talk to your daughter about her fears? It depends on where you live of course, but there may well be some further support available on the internet.

I do hope the web sites below will help to guide you & your daughter through this very difficult time.
www.bullying.co.uk  + www.girlshealth.gov/bullying 
Therapist C is a psychoanalytic psychotherapist with experience of working with relationship and many other issues.

It sounds like your daughter is suffering from panic attacks when having to go to school. It is crucial to find out what it is that is frightening her and making it feel unsafe for her. You have not mentioned how long you have been in France and whether your daughter speaks French. Unfortunately adolescents sometimes find it difficult to deal with those who are different from them and bully them or make fun of them and this is extremely difficult for the young person who is at the receiving end. The cause of this school phobia must be dealt with as quickly as possible so that the effect on your daughter is minimal. I would suggest that you find out what sort of psychological help is available for young people in your area. The headmistress or headmaster of your daughter's school should have that information.