I'm not sure what to do about this (if anything), mainly because it has been going on for several years now.
I have been d@ting my boyfriend for 3 1/2 years. I have gotten to know his family very well, and while they are all really warm, fun people, they are also extremely outspoken. Some members of the family have a tendency to make comments like "Oh, so-and-so? He's that nutcase from XYZ religion!" or "I can't believe there are so many idiots out there who voted for X." I am somewhat reserved and rarely discuss my political or religious views with people - so they have no idea that I may be XYZ religion or may have voted for X. I met them when I was 17 and less confident than I am now, so I have never said anything direct.
Here's where the assumption part comes in: I've discussed it with my boyfriend, and he says they just assume I share his political and religious views, since I'm d@ting him. He doesn't even necessarily hold those views anymore (he's not lived at home for a few years and his views have changed), but he doesn't think it's a big deal.
I don't like the rude comments they make (even if they don't directly insult me, they often insult my friends or family), nor do I appreciate the assumption that "she's d@ting him, she must be just like him." But I also don't want to hurt the feelings of these people who mean a lot to me. Should I just keep letting it go or is there a gentle way to tell them that their comments are offensive without getting into my personal beliefs? I think they may just expect me to speak up and debate with them, but no one likes a six-on-one debate...