This is a tough one but for me, letting people know that I have a stutter helps relieve the anxiety and more times than not people will open space for you to speak on your own terms and won't make you feel stupid. If you can't do this face to face the first time, try explaining it in a letter. Another thing you could do is find a few trusted people you can practice with or acknowledge the times you are successful in your speech and celebrate it. I remember this shame and fear all too well and I hope this helps