This^ I play out the conversation as if I were actually having it with someone else... Alternate routes, my reactions to theirs, that stuff. I replay what I'm going to say over & over before I make the simplest of phone calls. Before I go into the gas station. It's exhausting. But it generally stops when I'm actually having conversations with people- and for me, at work, it's conversations with lots of people... I guess my brain is just too busy to talk to itself then.