Medary.com

Study says that it's not always better to "express your feelings" after a traumatic event:

If the assumption about the necessity of expression is correct -- that failing to express one's feelings indicates some harmful repression or other pathology -- then people who chose not to express should have been more likely to experience negative mental and physical health symptoms over time, the researchers point out.

"However, we found exactly the opposite: people who chose not to express were better off than people who did choose to express," Seery says.

I think that this is simple group dynamics at work.  People tend to model their behavior after those around them--good and bad.  If you see someone else soldering on with a "stiff upper lip" you're more likely to do so as well.  If you see someone collapse into a blubbering dysfunctional pile of misery, you're more likely to do that, too.