1880 Austrian psychiatrist Joseph Breuer started treatment of Anna O. (Bertha Pappenheim) who suffered from hysteria. Not being aware of that, Anna O. enacted her early overwhelming observations and fantasies of intimate relationships between her parents, that is, she showed up what she thought her parents were doing. Many of these symptoms diminished or disappeared when in the treatment Anna O. recalled how they started and re-experienced her suppressed feelings. In 1895 Sigmund Freud and Joseph Breuer jointly published these findings in an essay Studies in Hysteria. It was the beginning of psychoanalysis.
Around 1892 vacationing in Alps S. Freud was approached by the hotel owner's daughter Katharina who suffered from anxiety attacks and shortness of breath. They talked just once, and Freud traced Katharina's anxiety to her witnessing adults' intimacy, that is, Katharina's anxiety attacks were return of her traumatic memories. She was disgusted by the sight of a man and a woman being intimately together because in the past the same man tried to seduce her. She though, "Now he's doing with her what he wanted to do with me."