Mary Trump, a clinical psychologist and niece of Donald Trump, told MSNBC Monday night that her uncle is a “destroyed human being” whose inflamed criticisms of Kamala Harris are being driven by a “defense mechanism” as a reaction to the vice president becoming the Democratic nominee. “Donald uses very frequently a defense mechanism known as projection in which he takes things that he unconsciously knows about himself but can’t bear and projects them onto other people,” Mary Trump told MSNBC host Lawrence O’Donnell Monday night on his show “Last Word.” “That has been happening with increasing f…