I say part one not because I'm planning a part two, but because I'm sure I'll think of more later on.
"Oh, I just loved being a (kid, teenager, young adult, senior citizen); those were the best years of my life!" Well, that's nice. And how was the food over there on Mars? Just because they were your best years- and I think you're making that up- doesn't make them mine. And face it, no matter how old you are, something will be going wrong in your life. If everything is perfect, that means you're dead. I consider the 'best years of my life' statement a slap in the face. It carries the connotation that if you're NOT happy being five, fifteen, fifty-five, whatever, it must be because you're a horrible person.
"Of course I think you're a good artist! You're my grandchild!" This is completley, totally, entirely hypothetical; do not believe that someone was actually tactless enough to say this to me when I wanted an honest opinion. Really. The connotation here is that you're not allowed to be bad because the grandparent's golden presence (or just existence) casts a haze over everything you do. In other words: you stink. If you want to tell someone they're good at something, and be believed, leave relationship references out of it.
"Aren't you glad you're an only child?" In the first place, I'm not: my sister died. In the second place, no, I'm not glad. I would kill for a younger sister. For a brother I'd consider extreme mauling. In the third place, this is one of those thoughtlessly tactless (the more I learn the more I think tactless and thoughtless are synonyms) things people say without knowing any of the background.
"So when will you have another one?" If someone ever asks me this when I'm in a bad mood, I suspect my answer will be along the lines of "Excuse me, my sexual practices are none of your business." I consider "So when will you give me some grandchildren" and "When are you going to get married" (unless, of course, you happen to know that I'm already engaged) to be in the same category. This is so not people's business. Back off.
"Well, I always just think that when a baby dies before it's born, it's like it never existed." And yes, someone said this to the Teacher once. When my sister died. This isn't just tactless, it's hurtful. And clueless. And buys you a family spot of immortal fame, even if we don't remember your name.
"EEEwww! I've never touched raw meat before!" Another hall-of-famer. It's not so much that I won't say this as that I can't. Especially not with a straight fame. When this actually happened (at a 'learning to be self sufficient' girls' camp cook-off), I kind of choked and then managed to keep a straight face long enough to point out that the fire would kill all the germs. As the Teacher said, she might not have touched raw meat but I'll BET she's not vegetarian.
"What about socialization?" Well, what about socialization? I'm against it, myself. This is the stupidest question I'm ever asked as a homeschooler.
"When are you due?" Why do you care, are you planning to be there, I guess I could use an extra labor coach or two-ooo-ooo! And yes, we have weird taste in Christmas music. We never listen to jingle bells either, unless under extreme duress or a supermarket loudspeaker. Anyway, this is one of the questions where unless you really do want to be a labor coach, or are part of the family, or are a close friend and want to finish something or other in time for the new arrival- why do you care? And why do you keep bugging me about it when you can't be bothered to remember for more than a few minutes at a time?