Need advice.
Saw the husband of a friend having dinner with a woman. He saw us. There were other friends in the restaurant, so many people coming over to say hi to us. Not him. He thought we were saying hi at one point, but it was the friend behind him. Awkward.
He later left without acknowledging us

Do we inform his wife?
Was the woman not his girlfriend?
Are we not being good friends by not informing his wife?