Why are all the majority of Atheist so bitter and vitriolic at times when they answers a question?

I am only searching for an opinion that will enlighten me.I require no sermon on the fact that I believe in something beyond the ken of the people who in reality can only say ,I dont know and I dont believe.If I was a visitor to this planet today I would reject religion totally for the mess it has created and to my fellow brothers and sisters in Atheism I dont judge you nor do I disparage you like the Norris penquir who alluded to the presummtion that I require a girlfriend.I have one already and her name is Sophia.I only want to know what you all think and surely its fair to say that only when you die you,ll know the true answer to the meaning of life and death.