OP, I am in the same situation as you, and I do think it is important to go. This is pretty much the only face time I get with my employer, so while he wouldn't fire me for missing the party I would be missing an opportunity to build that relationship.
It is very awkward, but if you can bring a +1, do. Mine was a dinner thing, so I just talked to my SO until we sat down to eat, then dinner conversation once you are all fixed in your seats is easier.
It is very awkward, but if you can bring a +1, do. Mine was a dinner thing, so I just talked to my SO until we sat down to eat, then dinner conversation once you are all fixed in your seats is easier.