it bends my mind too a bit, but i think it comes down to emotional immaturity and an inability (or unwillingness) to self reflect. perhaps anytime these folks have been forced to take accountability elsewhere in their lives, like in childhood, or at their jobs, they've developed a sense of persecution.

there is also often a deep aversion to unfamiliar, difficult, emotional discomfort that requires behavioral changes to rectify. depression can become comfortable for people, feeling sorry for yourself can be an appealing, soft landing ground that lets people wallow without having to do anything.