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We usually start out looking forward to a beautiful tree surrounded by perfectly chosen wrapped Christmas presents, but remember Christmas is not a showcase for your skills as wonder woman. Also, by allowing other people to contribute (albeit imperfectly), you'll add to their enjoyment and make Christmas even more of an event to be shared.
Trying to bring everything together at the right time.
Make contingency plans that let you go with the flow, even when your planning develops flaws. For example, soak-it-up canapes of a simple but fairly substantial nature mean if the oven temperature drops and it takes twice as long to cook the turkey, guests won't be ravenous or too tipsy. Let small children eat at their normal time. Other contingency plans…quizzes, a great film or comedy DVD.
You're exhausted…and doing everything!
Getting others to do more is a skill. Instead of automatically saying "Nothing" when people ask what they can do, think of useful tasks in advance. Can guests or family wrap presents, make or bring canapes, homemade mince pies (even if they've brought them from the WI stall). Or brandy butter? If they don't offer? Ask them anyway - sometimes people are just waiting for a bit if guidance. But don't forget the golden rule: once you've delegated, let the job be theirs and don't backseat drive!
Easy-to-make mistakes, such as leaving the giblets in or forgetting to make the gravy.
Your mood is more infectious than you realise. Being able to laugh at - or at least shrug off - things that go wrong immediately makes everyone relax, which in turn will make you feel better.