I used to feel this way too, I’d call myself stupid in my head constantly. When I stopped doing that and started to accept myself and f the people that were jerks my stutter got better, didn’t go away but got better. It’s a process to stop thinking that way. Whenever I had a bad thought about myself I’d immediately think “no, stop that” and push the bad thought away. Everyone has something ours is just more obvious. Sending good thoughts your way!