You Don't Eat WHAT?

Dear Mrs. Ditter, All my friends seem to be deciding that they can't eat wheat, or cheese, or some other thing that is a staple of most human diets.  Help me out here. What is the difference between a dietary need--like an allergy to peanuts--and a dietary desire--"I don't like to eat wheat because it makes me feel bloated"? Do I have to cook three different meals when I invite people to dinner? Run the menu past every single person (no eggs for her, no meat for him, she hates lentils, etc.)?  Or just make a nice dinner
and hope they damn well enjoy it? -- Frustrated Cook
Hmm. I'd go with option C: make dinner and let them make their own choices from the food in front of them. But that's probably because I'm occasionally fed up (ha! see what I did there?) with the cooking situation at my house. I cook for one wheat-intolerant person, one lactose-intolerant person, one vegetarian, and one person who must have chocolate at each meal. And we all know who THAT is. But I digress, as usual.
Your question, I don't think, is really about what is the difference between a dietary need and a dietary preference. Anaphalactic shock and mild bloating are worlds apart. If you know your dinner guest is allergic to shellfish, don't serve it. Your question is more about what does a good host or hostess do when faced with a social world run amuk, a world in which people seem to expect others to unquestioningly acquiesce to the latest food fad or imaginary dietary hiccup?
Well, there's always the unstated Option D: Stop inviting people for dinner! 
However, if you insist on being hospitable, you could ask when issuing the invitation, "Do you have any food allergies of which I should be aware?" That kind of sets the parameters right there: You're asking about allergies, not preferences.
Here's where control leaves your spatula-clutching hands: Once you have issued an invitation to dine, it's up to the invitee to say, "We'd love to come for dinner. Jordan is allergic to peanuts and I don't eat any animal products." Or "I only eat meat during a full moon; let me check my calendar." Or "I'm on a thirty day potato-free diet, but I can eat anything else." Or whatever they say. 
So if they say they're allergic to something (and remember, you have opened yourself up for that information), make sure there are other dishes they can enjoy. But don't fret about it. If you make six dishes and they decide that four of them are off-limits, well, that's their choice. You've done your part.
As usual in these sorts of situations, common sense and common courtesy can go a long way toward making such a dinner pleasant for you and your guest. And let me digress once again: I'm allergic to shellfish, and there have been plenty of occasions when I've quietly made a delightful dinner by eating only side dishes. Sometimes, no one needs to know...something that we all seem to have forgotten in our disclosure-crazed world.
Comments? Below. Questions? Leave them in the comments. Anonymous, as always, is just fine. And thanks for reading.