Belief in the coming final redemption is a fundamental principle in Judaism. In fact, any subdivision of Judaism i.e. Hassidut, Sephardic, etc., that does not believe in the coming and imminence of the final redemption is not considered part of the Jewish religion.
The concept is not merely about having a light at the end of the tunnel. It is about the revelation of G-d's Sovereignty over the world, and is the purpose of the creation of the world.