You see, God gave us Mitzvot (look that one up; it means Commandments, but the Hebrew word carries a much stronger connotation that I can't quite explain. However, look it up under the singular, Mitzvah) is not for a better life when we die. It is for a better life HERE. Judaism is a religion of the Here and Now. We could ultimately care less for what happens when we die. Even though a lot of Jews do believe in an Afterlife (I would say a majority), there are plenty who don't, and that is considered well within the norm for Jewish thinking.
The Torah says absolutely NOTHING about an Afterlife. The Writings don't say much about it except to talk about Sheol, the abode of the dead, wherein there is no feeling at all. There are some references that POSSIBLY point to an Afterlife concept in the Prophets.
Whether I personally believe in an Afterlife is beside the point. The point that I am making is not what I think. It doesn't matter what I think. It matters how I behave. Even if I don't believe in an Afterlife, or if I do, I am not going to change my behaviour one iota. I shall live as best a Jewish life I may. God said it, I do it, and try to find out WHY he said it. That is the nature of Judaism. If you have four Jews in a room you have five opinions. A joke, of course. But there is some truth to it. We are argumentative little fuckers, I'll say that much for us.