Talk to Psychologist on Depression

My younger sister is unmarried and has done M.A in English Literature. Her depression started with the stuff she studied in her courses 3 yrs back. She started reading a lot of novels based on negative thoughts and watched a number of horror and psychologically frustrating movies. She used to feel herself miserable all the time and blamed her parents for petty issues. Last year she asked my father to let her go on a motivational camp out of city for 4 days. Despite his unwillingness, father agreed due to her extreme desire. But a few months later another camp of same organization was to be held in hill station in extreme winter. This time father did not let her go but it came out to be a real challenge for us. She cried and abused a lot and then attempted to suicide. We somehow consoled her but then she tried to escape from home without telling anyone. We got to know about her intention and somehow got her confidence back. But now she asks us to let her go anywhere she wants and travel