It was in Budapest where Melanie began studying with a psychoanalyst and a new world opened up to her. Melanie battled with depression and ultimately divorced from her husband at the age of 38. After the divorce and with her young children and very little money she moved to Berlin and began to work with Karl Abraham & continue studying psychology. While learning from Abraham and his teachings about children and their psychological needs, she started to psychoanalyze her own children and learn from them. Klein was the first person to use traditional psychoanalysis with young children. Klein's views and ideas were not well received from her peers; at this time she was entering a world dominated by men and her theories slightly conflicted with the famous Sigmund Freud and his daughter Anna, which later would cause great debates and rivalries. Klein faced much opposition towards her ideas, but she continued to study and move forward with her beliefs about young children as she began to write and publish articles. Klein had a major influence on the theory and technique of psychoanalysis. In 1932 Klein published The Psychoanalysis of Children, it was acknowledged as one of the most innovative psychoanalytic writings to date. Klein is the inventive force behind "play therapy." She was pioneering in both her techniques, such as working with children using toys, and her theories in infant development. Regardless of the unending debate over her ideas she continued to work and Klein was 78 when she passed, living alone with her cat, it is said that she still had an amazing memory right up until her death, and also that she had many friends but did feel lonely and still suffered from and battled with depression.
She was thought to follow in the footstep of Sigmund Freud in the evolution of her theories, but in the aspect of Erikson's theory- her life mimicked many of the stages in his psychosocial theory. The hardships that she faced growing up- losing loved ones, and feeling unwanted, these stages in her development are probably what led to her depression