Can someone help me here?? I am upset about an irate customer I got again today?

Isn’t it odd how some things happen?? I wrote a few weeks ago about how some woman got all upset at me because she couldn’t return a monopoly game. Today I got one wanting to exchange one theme for another one since she didn’t like Star Trek(which is one of the the themes of the monopoly games we sell)and wanted to exchange it for a Transformers one, but didn’t have her receipt since she got it as a gift. Let me make clear here that this is Movie Gallery, which is mainly a DVD rental store. We sell one little case of Monopoly games based off of movies we rent out, like Star Trek and Star Wars, and we only sold two as most people just come here to rent or buy movies and games. Well, just like the last time I had to call my boss because I didn’t know the procedure on exchanges(I already knew the returns procedure thoroughly thanks to the last woman)yet since I am still new to this. So I called my boss and she walked me through the exchange. The woman was being sarcastic and obnoxious right off the bat by the way. There was nothing on the game on her account of course since she didn’t buy it. Everything was going okay until my boss told me we had to have a receipt so we could verify the purchase(since other stores like Wal-mart are selling those games too). She started off “don’t make me get mean blah blah blah. So just to make her feel a little better and to try to keep her from taking it out on me since I am only following rules, I verified it with my boss again. When I finally told her that my boss said I couldn’t exchange it without a receipt she went off screaming “YOU GUYS HAVE LOST MY BUSINESS FOREVER!” and stormed out. What is worse was unlike the last time, there were other customers in the store, and in line, which embarrassed me. I mean I DON’T make the rules. I myself don’t agree with all of the rules the company makes either but I still have to abide by them. I am only working there because the job market is tight and I can’t find something better right now. Please take your crankiness to corporate or something. I don’t make the rules. I hate working at this place to begin with but like I said the market is tight right now. I looked up her history there and she has rented a lot there so I don’t know why someone would go nuts over some board game which we have about 5 of in stock and she and that other woman were the only ones who bought any game. I am really trying to stay cool about this and not start being rude and mean about fat women(which she was). I have known a lot of nice fat women too so I a trying to keep from being Al Bundy here. Can someone give some counseling here. It is too late for me to call my therapist today and I am still irate about this.
Oh and the people behind her were firefighters who are also customers and whom she also chit chatted with and badmouthed me to.
Also, remember I want to get out of this job but I am having a hard time with it right now because of the economy.
So I am stuck.
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Not sure what you want. A customer got upset and yelled at you. Move on.
Don’t let one idiot make your life bad. She’s the person with the poor life. You’ll encounter many of these types of folks in retail, but you’ll also encounter good folks.
The firefighters probably were laughing at HER behind her back.
Remember that the only thing in this whole story is you can only control 1 person in this scenario…You. You can control you reaction to this woman. You can’t control her, her behavior, or what the people in the store were thinking. Only you can control you. So, you got stuck with a rude customer. She yelled, her behavior was inappropriate, and you are upset. Why do you let someone like this to upset you? Why are you allowing her to ruin your evening? Why do you even let her into your thoughts. You are allowing her to make you unhappy. You are in control of you. Let it go and be kinder to yourself.