Book about the grief of losing childhood/years to mental illness (fiction)

I’m looking for a book about the grief of losing childhood, youth, and entire phases of life to mental illness. Something that captures what it’s like to not come out the other side “okay,” to feel the weight of lost years, to grow up with mental illness and the deep isolation it brings.

A story that speaks to the feeling of being late in life because so much was spent just trying to survive, in treatment or active crisis. I don’t know if this is too specific, but I really need something like this right now, I’m processing a lot lol. Thank you!

Ps: hated year of rest and relaxation, it was the most infuriating pointless book I’ve ever read.