As for the third question. I can offer a theory. Emotions and underlying beliefs about yourself or relationships with other can either exacerbate your stutter or greatly diminish it. You have more anxiety and fear of rejection/misunderstanding with talking to someone new rather who isn't aware of your stutter or what is it is, versus someone who you've known for a long time and who you perceive is relatively knowledgeable about your stutter. Too often we come across people who view stuttering as a sign of nervousness, shyness, lack of confidence or some other generally negative trait. So there's that pressure to be fluent with these people, because we want to look good to others. And also, depending on you stuttering severity, you can't even explain to them the situation or that you have a stutter. So there a ton of anxiety and you recalling previously bad memories. I'm not saying it all due to your emotional state, but it can be a huge factor for why you're stutter with other people besides family and friends. Another thing you mentioned in your post, is that you stutter even with close friends. I'm the same way, and I think it's because of potentially a few reasons. I'm not too sure myself. But maybe it's due to the pressure we put on ourselves to be fluent, because we ourselves really don't like to stutter or have these physically stressful blocks. Every time we talk to someone, no matter who it is, we are secretly praying and hoping not to block because it's so annoying and aggravating. Also there's the fact that these are your friends and you treasure them. You want to have fluent, free flowing conversations with them because you're able to have better experiences talking to them and be totally present. You want to be easy to talk to, so they enjoy talking with you and you fully enjoy talking with them. I don't know about you, but when I block on words, it can be pretty distracting and I'm briefly no longer fully present in the conversation. I'm now focused on saying this word and overcoming the block. And it's probably distracting to my friends listening as well, or really anybody. Add up enough blocks and you barely have a conversation or one you really enjoyed, no matter who you're talking to.