If you are going to be a bastard make sure you have a good reason for it – even if it’s minor. A teeny tiny headache is more forgiveale than “I felt like being a bastard.”
Women have known this for centuries, and are perfectly willing to chalk up bitchiness to any number of female ailments that scare the bejezus out of us men. While PMS/PMT is a very, very real thing, it is also a scapegoat for any number of “I fet like being a bitch today” moments.
It is only fair that men take a moment every few weeks to do the same sort of thing for different reasons. A headache or stuffy nose is enough to excuse the worst mood.