Maxine, My Dysphonia is not as advanced as yours, but I have Essential Tremor and in some cases it is accompanied by Vocal tremors. As you said it is worse under stress or fatigue, and being out in cold weather. I have seen my ENT and he sees no nodules, but I intend to address it again this year this time with the Neurologist in January. From what I understand the nerves that control the vocal cords are malfunctioning. Some people have had luck with speech therapy, Botox and other procedures. For me it is certain syllables and sounds, and I don’t sing anymore because at certain pitches the words disappear. Good luck in your search for something that works for you.