You wrote, "Freud thought it was correct...and Einstein agreed. That's good enough for me."
Freud was a fraud, all but completely disavowed by modern psychiatry, basing his theories on the most slipshod scientific methodology ever perpetrated by anyone. You might want to reconsider using him as an authority on, well, anything.
Modern psychiatry is also a fraud (by your standards). So is most psychotherapy. Its practitioners are the modern-day snake-oil peddlars. The fact is mental disease and human suffering are beyond the ken of present-day knowledge.
As I said in a previous post Freud - despite his errors - was a genius and well-worth studying.