Do you love criticism? Probably not. Most people see criticism as a personal attack which triggers all kinds of defense mechanisms.
Actually, a business will pay big money to hire consultants to tell them everything they're doing wrong! They'll hang a suggestion box -- and if there's a chance to improve business even the words of the junior most are considered by the CEO.
So why does that same CEO get angry when he comes home and hears suggestions from his wife?
The answer is that he's focused on making more money, but may not be focused on becoming a better person.
Realize that every mistake carries with it a negative consequence. By helping to clarify the personality flaw that caused the mistake, criticism can save you from future loss. Your friend will tell you when you've got spinach stuck in your teeth, while your enemy will smirk and say you look great!
As the Sages say: "Better the criticism of a friend, than the kiss of an enemy."