Well, there are certain times when you need to vent your anger, and let it rip   and other times when you need to control yourself, and keep your lips zipped. Here's how to know the difference.
  • Keep it zipped when someone cuts in front of you at the grocery store. I know it's not fair, but in general, blowing up at a stranger is a bad idea. That comes from the book "The Winner's Way". Not only do you not know how that person will react, but you also don't know the reason behind their rudeness. So instead of fuming, grab a magazine in the checkout line and chill.
  • The next scenario: Your boyfriend wants to invite his buddies over to your place every Sunday to watch football on your plasma screen TV. Keep it zipped or let it rip? Let it rip. Expressing your frustration when you first feel it is better for your health and better for the relationship. If you don't your resentment will build and every aspect of your relationship will feel it. But wait until his buddies leave to express yourself.
And another time to keep it zipped is when your boss takes credit for your work in a meeting. At least keep it zipped until the meeting is over. Undermining the boss' authority in front of others will make you seem defensive and aggressive. Instead, talk to the big cheese privately, and calmly say something along these lines. "I'd like to be recognized for my work. Can we discuss a way to make that happen?"
If you'd like to go further, the book is called "The Winner's Way" by Pam Brill.