One problem that causes mental health issues in celebritities may even be their entire essence...being a celebrity. Their lives whether they like it or not, slowly turn into shows for ppl, their fans. And in time, those lives build up to have the drama and conflict we see in the stories they act and work in.
If you think about it, it’s the celebrities who have some sort of rumor or controversy about them that are most remembered.
They end up becoming the puppets of ppl. No privacy, no choice in the way they live their lives - everything is being judged and altered by the audience. They are characters in a choose your own adventure book. And that changes and hurts ppl from being ppl.
I think a literary analysis of the song 'Gasoline' by Halsey will give you some more inspiration and insight on the topic.