Brene Brown (TED talk on Vulnerability and another one on Shame) says that if we try to suppress negative emotions (sadness etc.) then we end up suppressing all emotions.
During one of the TED talks, she put up a picture of a "swamp of sorrow". She said (something like) "We need to get into the swamp of sorrow. Not to set up house and live there. But to walk through the muck and get to the other side"