quick - gratefulness and hurt
from a thought strand: i think they've just experienced so much hardship in their life that those difficulties have stuck in their mind and stopped them from realising there were also happy moments, especially since their hardships seem like a continuous part of life as opposed to a one-off terrible experience.
you know, "with hardship comes ease" but instead of thinking of the "ease" coming after the hardship, recognising that there are different types of ease that one might be experiencing at the exact same time that they experience hardship in another aspect of their lives
people that have gone through traumatic moments perhaps have some struggle with recognising which areas of their life they may be experiencing ease during a time of hardship. black and white thinking, putting an entire period of your life as "this was when i had a bad time", not realising that most of life is a mixture of black and white, and rarely will you find there's such times which are unapologetic periods of happiness or sadness.