People of religion are as a whole, welcome to the idea of other religions, that, for example Christians believe in one God, but accept that the religion of Hinduism believes that there is one god in thousands, and thousands in one.

What I struggle to comprehend is how although these people can accept each other's religion, they cannot accept atheists in not thinking that if we stray of some 'path' that we will all be doomed forevermore to burn in an eternal hell.

To the extent that what you say is true, I think that many people equate religion with morality and believe that without religion you have no morals. I think many people also assume that atheist are anti-religion (and therefore anti-them).

This is unfortunate, and one of my goals in life is to demonstrate that atheist can be just as moral and non-judgmental as anyone else.