You are not bad parents. You sound like you have a gifted possibly ADHD kid.
For social skills - here are some things that were reecommended to us:
Drama class- if they have memories good enough to memorize their lines, drama might be a great way to get them to acknolwedge their turn, someone else turn and social queues. However, it remains to be seen if they can remain on stage long enough to partake.
Dance/Exercises to help strengthen sides of his brain that may be weaker. Does he have any other issues that could be neurological?
Try giving him coffee and or sugar free Mountain Dew/Dr. Pepper -does it calm him down? Good chance he has ADHD if stimulants calm him down - and you can figure that out before you go to a doctor of a real diagnosis and real drugs.
Also - see my other post under "learning disorders" on the Future of ADHD treatment for non-drug altenratives.
Nearly all the adults I've spoken to that had ADHD when younger have grown out of it. I still think Maturity is a HUGE part of the issue.
Also - I have started to explain to DS6 that "being truly brainy/clever/intelligent" also means knowing HOW to behave the right way for certain people. So now he's thinking a little bit more "craftily" regarding his beheavior in school. He takes pride in being "brainy" - so see what your child takes pride in and try and twist it to help him see his behavior in a new way.