This is a hard one! I do believe that wires could have been crossed, but I do not think that the husband should have replied with, "you were not invited". He should have said, let me check with....(the wife) and get back with you.
I do not think that I would go at this point, it would be awkward. I would however, try to go on with the relationship and forget about this whole situation after the party.
:grouphug: