I was a severe stutterer. Never a fluent sentence. Blocks that lasted longer than I had air in my lungs. When I went back to speech therapy and was serious about it, I got fluent in under a year. Be honest. Be dedicated. Don't conceal or hide. Therapy will only be effective if you give it an honest effort. Anything you withhold or conceal will only impede your fluency. I've been fluent for more than two dozen years now. I had a severe stutter for nearly that long.