Not all therapy is created equally, nor are all therapists. Sometimes getting a great therapist is the luck of the draw. If you're not having a great therapy experience, it doesn't mean therapy in general is bad, just that perhaps you haven't found the right fit yet.
The Emotion Machines points out 3 reasons why therapy may be failing you (or failed you in the past). Take a look & see if anything rings true. Now you know what to look for!