In case you never watched a sitcom growing up, it's ridiculously easy to re-frame a dysfunctional family as a hilarious family. Growing up, my parents ran a campground that was constantly occupied by weird burnt-out hippies with nowhere else to go--many of whom only bathed once a month! Do you think I let that stop me from bringing girls over? Of course not! In fact, they were dying to meet the people from the crazy-ass stories I had told them about my life.
Remember, what you feel, she feels. If you think your family is embarrassing and stupid, she will feel embarrassed and stupid. If you can find humor in their dysfunction, not only will she also find humor in it, but she will find you unequivocally more sexy for your outlook.
Of course, the long-term solution here is for you to accept your family as they are, love them, and start not giving a shit what the girl thinks about them

Hope this helps.
Your boy,
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