I believe fame become a physical addiction over time especially if one experiences the highs and lows. Dopamine or other hormones are produced in some individuals head when they feel famous that they must then try to achieve again even with extremely risky behavior. If they can’t have their fix of fame “chemicals” replace that need. That is why many a star becomes addicted to other substances when fame is fleeting and others will go any reality show. Fame is like other addicting chemicals/behaviors where some can handle it and others fall off their wagons.