For me, my anger was a defense mechanism. Stuttering hurt. It hurt a lot. It also greatly impacted my sense of self worth. Being anger was a coping mechanism. Not a healthy one. And I held that anger for a long time. Through my development as a youth and a young man. Even though I am fluent today, that anger lingers. It's part of me. My anger and my speech were really two different things. I had to recognize that. I think the suggestion by u/fljboy to talk to someone is really sound advice. You have to let it out. Find an outlet for your anger as well. Channel it into physical exercise or some other constructive outlet. I *always* advocate for speech therapy as well. If you can make some progress towards fluency, it can only help.