I Totally get you. I’m almost totally fluent in casual conversation and on the phone, but I can’t explain anything, request anything, express my needs or feelings without seriously stuttering. Stuttering has a neurological cause which potentiates any emotional damage. In my case I wasn’t allowed to request anything, or express my desires in my childhood. Nobody gave a damn. My psychotherapist believes that caused my stuttering when those instances occur. I also stutter badly when speaking Spanish, a language I learned in childhood. In that case I think there is additional stress in translation to English. This complicated disease has a different pattern in each of us. You have your particular issue which is really unique to you. The causes are tied to your neurology as well as emotional issues that you ( we) might not even be aware of. Have you sought any help with your stuttering. I’m 78f and I’m, for the first time, seeking speech-language therapy. Even at my age it might help.