Sometimes I feel that some fans are too heavily invested in their faves emotionally. They end up not handling criticism well and it impacts their mental health. And then if a scandal breaks out or the group disbands, it's crushing. I feel like this is more common in kpop than in other parts of the music world. I also have noticed that kpop seems to attract many fans who have difficulty in other parts of their life and may see kpop as a way to fill other voids or as an escape.
I think companies actually target this and market to increase this kind of emotional attachment (dependency). Sometimes it's less about the music and more about how appealing the idol is as a person and the group as an idealized pseudo family unit. They also play into a person wanting to feel like they were able to overcome adversity or achieve a win by tying fan behavior with a group's accomplishments.