Girl, You Vent About Me??

Is it okay to vent to your friends about other friends? This week we get really candid with each other and let it be known that we both vent about each other. We both feel it's healthy to do so, but it does feel a little weird to know that we do this. Is it a betrayal to vent to someone else? Should you only speak to the friend you have an issue with? That's the question.