Imagine how Robbie Travis felt. He waits tables at Libertine, a high-end restaurant just outside St. Louis, and his ex insisted on coming in just a few days after they'd broken up.

Like everyone else, waiters and waitresses have to show up for work on days they'd rather be anywhere else. But it's especially tough to shrug off a bad mood in a job where people expect you to greet them gladly.

"You have to fake it a little bit," Travis says. "That's what pays the bills."

When I've asked servers lately how they were doing, the answers ranged from "hanging in there" to "excellent — no, great!" No one has come out and said they were lousy.

But when I asked what it's like to have to wait on people when they've been distracted by bad news, every one of them had a story.

"I've had plenty of bad days. I've had deaths in the family," says Emily Nevius, a waitress at Longfellow Grill in Minneapolis. "But it's work and you put your work face on."

Similarly, Laura Abusager, who has waited tables in Bloomington, Ill., for the past five years, says she tries to put on a "poker face" when she's dealing with issues in the rest of her life. She feels like her work doesn't suffer, but she says her coworkers can always tell when things are going wrong at home or in relationships.

The customers, too. "I feel like I get better tips when I'm in a good mood," Abusager says, "and when I'm in a bad mood, it's like they can sense it."

Restaurant owners and managers know servers who can be fun and flirty or at least chatty and attentive not only get better tips, but add to the quality of the dining out experience in a way that's crucial to the bottom line. (Indeed, psychological research supports the idea that friendlier waiters get better tips.)

Except for real regulars, customers don't know about their waiter's life and don't want to know about it, says Meredith Berkowitz, Travis' coworker at Libertine.

"We do meetings here where they tell us to leave our problems at home," says Davee Crain, a waiter at Geno's East pizzeria in Chicago.

Performance matters. There's an old cliche about people who wait tables all being aspiring actors, but it's clear that acting is a big part of their day jobs.

"It's an acting job," Crain says. "It's a mask."

Waiters who are having a really bad day can always borrow a trick from Ann Patchett.

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