What you say in session -- and even the fact that you are/were attending therapy -- is kept totally confidential and will not be discussed with anyone without your prior consent. In accordance with existing laws, confidentiality is only broken if a person presents a danger to himself or others.
Sometimes therapists may need to discuss some aspects of your case in clinical supervision (with an accredited supervisor who is also bound by confidentiality). Supervision for all psychotherapists and counsellors, especially those in private practice, is required by most professional psychotherapy associations as it helps to maintain high professional and ethical standards. If any aspects of your case ever come up in a supervision session, your name will never be mentioned and your personal details will be changed to make identification impossible.
At Balanced Lifestyles Counselling in Prague I abide by Ethics for Counselling and Psychotherapy of the British Association of Counselling and Psychotherapy.