Don't forget him

Hard as it may be for people to believe- I can barely believe it- there are time when I don't know exactly what to do or say and that I have a hard time being grown up and mature (when your laughter stops, please read on).
A few evenings ago we were out to dinner with Dakota, some family members and friends. Among the group were two children besides Dakota, a boy and girl- both about his age. The seating got shifted around so it turned out the other boy and girl were sitting next to each other and Dakota was across from them. For 95% of the dinner they didn't talk to him or include him in their conversation. The time he was included was because I started a conversation with Dakota and they wanted to get in on it. I watched his face as they talked and excluded him and it was so sad; but the worst was yet to come. The little girl went to the bathroom and Dakota took the opportunity to talk directly to the boy and ask him questions- without much response. He kept trying as best he could but when the girl was on her way back to the table he said "oh, she's back, never mind", and went back to saying nothing. This broke my heart. He seemed to understand quite clearly that they didn't want him in their conversation and he assumed his place in the back of the bus.
I am ashamed to tell you that my feelings vacillated between anger and the petty desire to make them feel bad for hurting my child. I had to keep reminding myself that they were children and I had to help them understand and behave differently; not necessarily just because Dakota has special needs but because they should treat everyone with kindness and practice inclusivity.
The next day I asked him if it bothered him when this happens. He said it didn't and that he just listens and waits for a chance to talk (and all this time I thought he was impatient). I didn't ask him what about if he never gets a chance, but I did ask him if he understood what they were talking about. This made him angry - as though what I was suggesting was that he is stupid. I wish he could/would talk to me more about what he feels...of course there's always the chance that I couldn't handle it as well as he does.