Most of them have deep rooted self esteem issues. You got to be aware that when a person is feeling insufficient in any aspect they always act the opposite of what they are thinking about themselves.They act like they are totally competent in that area but actually aren't. Like when they see other peoples flaws and make fun of it -this is to make themsleves feel better about themselvesThey do this by demeaning others bout the same issues cause they like to think that others are worse off then them.It also makes them think they are not alone in their misfortunes.In the end it's not about you, it's about them so don't take it personal.They are simple creatures who need some urgent attention-but beware never give the the satisfaction of attention then they won't leave you alone.Think smarter move on, be the bigger person and let it go.Best wishes