My father taught me to be nice first because you can always be mean later. But once you've been mean to someone, they won't believe the nice anymore. So, be nice; be nice until it's time to stop being nice, then destroy them.
"Once you've accepted your flaws, NO ONE can use them against you." It's one of the hardest and most liberating things at the same time, to accept your flaws.and more so, to shine a new, bright light on these flaws.