I often think of Tony Hsieh (Zappos founder/CEO), who was a much more grounded and humble person before he became extremely wealthy. Perhaps he had the tendencies/propensities (that ended his life) dormant all along, and his wealth suddenly boosted those deadly habits.
His story really is a tragedy. We have a long way to go to properly treat mental health issues as a health issue (no different than allergies, cancer, etc), and to eradicate the stigma of acknowledging, accepting, and ultimately addressing them.
You can't be a billionaire without pathology. The power, unlimited access to every resource, the inherent isolation, security implications, factual immunity to most consequences, morbidly twisted self-efficacy, the ethical dissonance of having it all while others starve... the human brain evolved adapted to scarcity and existential group boundaries to check on social pathology. These guys are holistically unchecked, inherently dysregulated on every axis. Their brain is constantly in an extraordinary, extreme state, trying to reach homeostasis for a life that couldn't be more distant, trying to find a model of reality which explains the abnormal signals it is getting.
Sometimes I think if Tony had given all the wealth away, he'd still be here. A cautionary tale.