Ever notice that in spite of all of the "Joy" and "Peace" and assorted warm fuzzy shit all over creation in December that people are less kind this time of year?? Rabid shoppers in a Wal-Mart trampled an employee to death on Black Friday and then continued shopping for Christmas presents.
No matter how much you try to remove yourself from the frenzy, you are affected by it. So many obligations, including travel, relatives that work your last nerve, children who don't know how to adapt to the changing environment and the patience of a gnat, plus the budget-busting presents is enough to wear anyone raw.
No one is perfect. Everyone has a black-cloud-over-the-head-but-I-have-to-put-on-a-nice-face-anyway kind of day. Everyone has THAT ONE BUTTON that always gets pushed. Everyone has that last straw that breaks the camel's back. Everybody snaps and let's someone have it once in a while. I'm having quite a few of those days myself for reasons I may go into in the next few weeks. Even Benedict XVI and the Dalai Lama lose it once in a while.
But here's the thing: a simple apology makes any bad situation better than before. The longer you put off that apology for losing your cool, the worse the bad karma will fester. The quicker and more sincere it is, the better the outcome. A lot of people are afraid to apologize for an error in judgement because they think the reaction will be worse than without it. Not so. That's a lesson I learned the hard way in my own life. The fear of being pummelled after an apology is always overblown.
So if you want peace on earth, like the hymn says, "let it begin with me". You don't have to be perfect. You just have to do the right thing when you're NOT perfect.
In short: if you fuck up, then fess up. It's good for the soul. Especially yours.