I do understand where you are coming from.

If only my name was on the invite I would question whether the rest of my family was also invited. I personally would check with the host, however I would feel really embarrassed that I had been put in a position where I had to ask. I also think you should have explained the invite situation to your friends. If you wanted to keep numbers low, you should have just excluded the group of uni friends.

Enjoy the party! I've been to a few recently and they are bedlam!