Dear Friendly Atheist,
Thank you for your honest question. If you do not believe in Heaven, then you most certainly don't believe in hell, so that's a moot argument.
If more people here were honest, they would say thay have the same question, even though they consider themselves to be Christian.
Why go to heaven? Well, honestly, that's not the point. As a Christian, I do not hope in a place, I hope in a being. And this is no ordinary being. This being made me, gives me life and knows who I am.
However, this being is not static. He is deeper than any one or thing can ever imagine. Yes, I would admit that if being in Heaven were static, it would get dull. However, this is not the case.
Have you ever had a favorite food or beverage, like a milk shake, that you were disappointed at finishing and wished there was more? Well, this is what Heaven will be like. Only, there will be no bottom to the "milk shake" and we will never get filled. But that's not even the half of it. The "Milk shake" gets richer, creamier and just plain better the more we consume. This is how that being is. He is beyond knowing, and yet invites us to know Him anyway.
Now, this is what I believe. Of course you are most free to disagree. I have no proof beyond my own faith, much like your own atheism.
In passing, I question your own atheism, ever so gently. Why are you here, in this forum? I would think that a true atheist could care less for any thing dealing with mans spiritual condition. If I were an atheist, I would content myself with being an atheist. As a Christian, I do not frequent non-Christian message boards and ask probing questions about atheism. I am satisfied that what I believe is true and live my life accordingly. Just a thought.
I'm glad you stopped by. May you find your peace.
Peace.
Peter