My AS son can be the same way, with both the boundary issues and the spelling / grammar. Many things are simply harder for him, because his brain is wired uniquely, and many other things are easier. AS is a mixed bag condition, isn't it?
If you don't mind being touched, ask your friends to use a touch signal system, or maybe a firm set of words, or both to get your attention when you are being too loud, too in their face, or too physical. A simple tap on the shoulder, or a stated "too much!" or "too far!" should do it, as long as you are willing to listen or feel for that signal. We've used many signals like that with our son and they do help.
Life is a learning process for everyone. Ask your friends to help you learn.
While you shouldn't have to worry about the spelling and grammar when you are doing social posting, it seems that some of the members here are very sensitive to it, in the same way you might be sensitive to bright lights or very loud noise. If you use a browser with spell check built in, like Firefox, it will help.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).