Even the guy who owns this site admits a therapist does not know if therapy will help a person or not and that they may not be able to help. It is under something like 10 Things Your Therapist Won't Tell You.
". I honestly don’t know whether I can help you or not.

Most therapists honestly believe they can help most people with most problems. However, until you get in there and start working with a therapist, a therapist can’t really predict whether they’ll be able to help you or not. Most therapists believe they can help anyone who comes to them with a specific problem they’re trained or experienced to handle. However, every single individual is unique and there are few reliable predictors of any given therapist’s success with any given client."
http://psychcentral.com/blog/archive...wont-tell-you/