(LifeWire) -- Think twice before accepting an invitation to a party. That's the lesson Tonya Bowman, 39, learned recently after a birthday bash for a newfound acquaintance at a pricey sushi restaurant.

Don't be bullied into paying for someone else's meal or drinks if they invited you, psychotherapist says.

While Bowman ordered economically -- rice, miso soup and tea -- everyone else acted as if money were no object.

"When the bill came," Bowman says, the birthday girl "smiled and made a big production by way of a toast, saying, 'Thank you all so much for my lovely birthday dinner. I really do appreciate it. You guys are great. Here's to you!' Then she just sat there, waiting for us to decide how to split the bill."

The bill for the birthday girl and her seven "guests" came to a whopping $3,450, which someone suggested splitting evenly. That worked out to $500 per person, plus tip.

"I almost started crying," says Bowman, a municipal employee in Oakland, California. "My heart was racing; my face felt hot. I was embarrassed, humiliated and angry for having been put in that position in the first place. I wasn't told that I would be helping to pay for her dinner."

When the bill was being passed around, Bowman panicked. "I simply put down $50 near my plate and excused myself to go to the restroom," she says. "I walked right by the restroom and out the front door."

The acquaintance sent Bowman an angry e-mail.

"She wanted me to know that I totally ruined her birthday dinner because she ended up having to cover the $450 that I was supposed to pay. She said she had planned to use that money on a spa day for her birthday and now she couldn't because of me. She asked if I could please pay her back, and if I didn't have the money right now, that was OK, because she would be willing to make payment arrangements with me.

"I didn't pay ... and she's no longer my friend or acquaintance."

Linnda Durré, Ph.D., an Orlando psychotherapist, says Bowman's story isn't unique.

"It's appalling what people do and how rude and insensitive they can be," she says. "I've heard stories about adults giving their parents an anniversary party and the parents getting stuck with the bill."

Surprise! Now pay up

Rachel Mays, 31, is still shaking her head about a surprise party she attended for a friend's birthday last year.

"We all got there at the determined 8:30 p.m. start time, and there was a fabulous open bar. Then, we were asked whether we preferred chicken or beef for dinner," says Mays, the owner of Bread and Butter Public Relations in Los Angeles.

Mays and her boyfriend were surprised dinner was being served at such a late party. Not wanting to be the odd couple standing in the back, they ordered anyway.

A few days later, however, the host told Mays she owed $120 for dinner and gave her an address to which she could mail a check.

"I ignored his first e-mail," admits Mays, "but when I received the second, I let him know I wasn't working at the time and frankly, thought it was tacky to not mention these details when he sent out the invitations." Mays didn't pay, but says she now avoids gatherings where she knows that person will be present.

Elayne Savage, Ph.D., a communication and relationship coach in Berkeley, California, says such situations leave people feeling disrespected and manipulated. She says an unpleasant surprise "throws us off our center. We expect our friends to treat us with the same consideration and understanding we would show them. It is very disappointing when this does not happen."

BYOF: Bring your own food

Melinda Williams, 48, owner of a public relations and advertising agency in Chester County, Pennsylvania, was thrilled to be invited to a neighbor's pool party cookout soon after moving to the neighborhood. Then she read the invitation's fine print.

"I remember it saying something to the effect of 'We supply the paper goods and pool, you supply the rest,'" she says. So Williams and her husband came prepared: "We brought a cooler with a full London broil and side dishes -- enough for everyone at the party."

When they arrived and saw a row of coolers by the pool, Williams says she and her husband opened one up and helped themselves to beverages, assuming that they were to be shared. "We were quickly chastised by another family (and told) that that cooler and beverages belonged to them," she says. "We couldn't believe it!

"We waited for about two hours and they never started cooking anyone's meat, and we had a small baby at the time, so we just left our food and cooler there and went home."

How to party without hurt feelings

"Situations like this can cause deep rifts in families and friendships that may be irreparable," says Durré. "I suggest being up front from the start. That way people aren't surprised, hurt, angry or resentful, and relationships can be salvaged."

She offers these tips to avoid sticky situations:

• Talk to your host: If costs concern you, talk with the party planner before you RSVP. Durré suggests saying something like, "How generous of you to host so many people at the restaurant," so that when you accept, you're acknowledging that you are guests -- not paying guests.

• Be direct: If it's a family member or a friend you know well, don't beat around the bush, says Durré. "You may just want to be more direct and say, 'Are you covering the expenses by yourself or would you like us to share the expense with you?' That way, there are no surprises."

• Be honest: If unexpectedly faced with a bill, you're under no obligation to pay it. Durré offers this script for people who want to take a stand: "When I'm invited to a party, I assume that the host is paying for it. To learn that I'm responsible for all or part of this is rather unexpected and rather off-putting. I wish you had told me beforehand. I'm really under no obligation to pay for this and I resent that you didn't tell me in advance."

LifeWire provides original and syndicated lifestyle content to Web publishers. Sarah Jio is a freelance writer who has contributed to "SELF," "Glamour," "Marie Claire" and many other publications.

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