For me there have been a few things that have helped to lesson my anxiety drastically. 1. Remember that people dont think much of your stutter besides simply acknowledging it. 2. Even if people do think about, who gives a fuck about what they think, if they can't accept you for the way you are then why even bother with them 3. This is probably the most important, try to push through your anxiety, yes sometimes it feels impossible to but you have to try, try taking every opportunity you have to test your anxiety, trust this helps majorly... I used to have pretty crippling anxiety paired with a severe stutter, then I tried those three things and both my anxiety and stuttering got better... I'm not saying it cured my stuttering or anxiety, however it improved them tenfold