Are you cold or do you wear your emotions on your sleeve?

Repression is an emotional tool.  An effective one, even.  If your boss says something rude to you, it is probably best to push the emotions that those words caused down until you can process them without  punching him or her in the head.  Punching doesn't usually result in positive outcomes.  

Many people use repression as their main emotional tool.  And that's a problem.  It leaves them filled with emotion for which they have no outlet.  And that leads to all sorts of other problems.

There are (at least!) two different ways to repress your emotions.  One is to allow yourself to feel the emotion before you repress it.  People who do this are said to wear their emotions on their sleeve, because other people can see the pain they are causing themselves by repressing.  It hurts.  It's obvious.  But usually these people don't know what else to do.  (I used to do this.  Now my emotions are commonly still obvious to people, but that's because I choose to let them see them, not because I can't stop myself.)  They have a taboo in their brain that prevents them from just expressing what they feel, when they feel it.  The result is pain.

Another way to repress your emotions is to push them down without ever allowing yourself to feel them.  People who do this are usually called cold, because they seem disconnected from their emotions.  People who do this are usually more effective people because they don't have pesky emotions screwing with their efficiency.  But these people usually also have a hard time learning to express their emotions.  I think it feels alien to some of them and probably weak to others.  Maybe both.  

In the end, the two forms of repression are just different sides of the same coin.  Both people believe they should not express their emotions, so they don't.  And for both people, the end result is the same:  pain.  And for both people the solution is the same: Express.  Express, express, express.  Feel it and express it.