Some people struggle to the point of mental illness because their boundaries aren't well developed, they can't protect themselves from the emotions of people around them.
It could be neurodiversity, perhaps autism or a trauma background.
I agree with this @picklemewalnuts, but it doesn't make them "Empaths". It means that they could do with support and help to deal with their pain and develop the healthy boundaries they need to protect their own MH. Self proclaimed Empaths OTOH, seem to think they have magical healing abilities.
Empathy is not magic, it is an innate thing in people. Like anything else, some people are better at it than others. Those who are good at empathy respect the other person enough to allow them their own feelings and thoughts without intruding upon them or appropriating them.
And certainly not by over emoting and claiming it's a mystical power.