What would a psychoanalytic person say is wrong with a girl with a negative outlook on life?

Well, I am a psychoanalytical person AND a girl with a negative outlook on life, and I'd say what is wrong with a girl like that is maybe something bad happened to her once and she never fully recovered from it. It could be one single event, like an assault, or ongoing events such as abuse (in either emotional or physical form.)

Some people may naturally have a negative view on life, but this is not common. The most people who have this negative outlook are people who have lost their faith in life, in the outcome of life, and see nothing positive for their present or their future. Sometimes you cannot help people who have lost too much this way, because their viewpoint is corrupted by their own mental distress.

Most people would say avoid negative people because they will only bring you down. I say try to encourage that person to feel better about who she is before you ignore her completely and fulfill her prophesy that all life is negative and worthless crap. You only add to it when you ignore it. IF the person does not respond to your efforts, you have to leave them be, because they cannot become well unless they accept themselves and progress forward instead of clinging to a negative past or present.