Yes, I block on every single word with friends and family too. The only time I'm fluent is when I talk to myself out loid in an empty room. I'm not way too nervous when I speak. Even when under the influence of Benzos or alcohol my stuttering doesnt decrease. I already meditate twice a day and practice my costal breathing. Dont forget i'm much older than you. I've tried all of this generic advice and a lot of alternative approaches too.