It's hard when people are unfairly critical of our work. You're already thinking smart by not immediately responding with your initial emotional reaction.

If I'm a potential guest and I see an unreasonable negative review I actually become more interested when I see the owner respond politely. If I see a location has only positive 100% scores I automaticly devalue all the positive comments because I assume the negative ones are being censored.

Some people just like to complain, if a future potential customer is turned off by- I couldn't read or follow instructions, and I have no self control towards what I stuff in my face... you probably don't want to deal with them as a customer anyway.

Negative feedback is also a good chance to improve your business practices too. If the information is too long and boring to read maybe you can highlight and shorten the presentation in your communications. I always try to be polite to everyone, but I also assume that everyone is easily distracted or tired or just plain dumb. Some people need more handholding than others.

Don't forget your business is not you. You will never make everyone happy all the time. They are allowed to be disappointed, you can try to reduce the disappointment but it will never be eliminated.

Good luck, keep at it!