I have a coworker for whom I am team leader. I am not his "boss," but I do pass work to him and he sees me as a professional mentor, and on several occaisions has said that I am one of the reasons he stays, because he likes working "for" me. On that level, we get along fine. He is also a homosexual who shares a house with his "partner." This partner's birthday is in the beginning of December, and my coworker has invited me and others to their house for a surprise birthday party. There will be plenty happening at the party - drinking, etc. - that I would not agree with, but if that were all, I would go and put up with it. But does attending this function voice an approval of their relationship and behavior? Should I go? It would be easy not to, since it is the Christmas season, and I will have plenty to do. What should I do?