They are speaking a foreign language and they are completely oblivious to this fact. No one will notice that you were there anyway, including your techie. Parties dominated by techies are truly exciting experiences. If a techie was forced to bring his SO, he will feel obligated, however, to forego technical discussions for at least the first ten minutes. He will tell you to simply inform your boss that you won't be starting until then.
Techies are very well read.
They devour books and articles on such exciting topics as memory management, VXD's and debugging but give them a book on relationships and watch the panic spread across their faces. Mention a couples workshop you think both of you should attend and watch those deadlines move up. At some point in their relationship, the SO must reveal to the techie that a romantic holiday does not entail bringing along a portable computer, stacks of computer magazines and a trunkload of listings. Expect any proposal to be very practical. If, at some point in your relationship, you decide to have children, you will have to fit baby-making in between compiles.