But you, as a family member of the person concerned, have the right to know the general situation, so I decided to analyze it for you. As for whether you can accept it or not, it depends on your tolerance.
As the saying goes, everyone gives her that name, and that won't be empty. Public **** toilets + public **** cars, in our lives refer to an essential part of our infrastructure, and their use is geared towards all citizens, which means all people can use them. So by referring to a person in this way, the meaning is obvious. It means that this person's life style is rather casual and open, and she can have sex with anyone as long as she wants to. The word "sex" in this context means "sexual relations". So the answer you're looking for is - your mother had sex with other people, and a lot of it.
I assume that you are currently a single parent, as no man would be able to accept such behavior from his wife. As for why your mother is doing these things, maybe she has a field day, or maybe she is being forced. Because the owners of places like beauty parlors have more or less a bit of background.
Now that you know the answer, I think you can find your mother to talk positively about this matter, your distress, anxiety and she said. Also find out what her initial thoughts are. If you can, suggest her to change her job and have a good life with you.