I would attend most religious rites for people I care about, as long as I wasn't being asked to do anything inconsistent with my own beliefs. The only religious ceremony I can think of that I wouldn't attend is a bris, but there might be others. I wouldn't sit through a regular service, though, unless I was sure I'd be comfortable with the message being preached. I have friends who belong to churches that I don't have huge differences with (aside from the whole existence of god thing ) and I would be comfortable listening to a service if it was required to attend the ceremony. But I wouldn't be willing to listen to fire and brimstone or certain political messages.