Anxiety 100% has a huge impact on stuttering severity. Most people who stutter stutter much less or not at all when talking to themselves. However, there's good news, if you have developed a stutter as an adult (or at least not as a very young child, which you do not sound like you are)... it is probably is something you'll be able to work your way out of. I'm not an expert in acquired-stuttering (that's probably not a real term), but I know that most of the people who "don't stutter any more" are people who started stuttering when they were older. Most people who start stuttering when they are under 5, do so for the rest of their lives, to one degree or another. Anxiety control is the big thing. I would focus on that. Fix the anxiety, and the stutter will take care of itself. I know that's a hell of a lot easier to say than to do, but at least you know what to focus on. If you can, I recommend going to a therapist for the anxiety.