Deep down, we know this to be true but often talk ourselves out of it. The source of all things, the highest state of existence, the absolute reality, it all exists within our heart. What an incredibly uplifting feeling, to know that we have the divine spirit right here within us. One of the oldest upanishads, the Chandogya Upanishad describes this with great beauty.
Many people go through their entire lives waiting for heaven to see God. Without ever looking within themselves they waste lifetimes looking for the necklace they are wearing.
There is no reason to ever feel depressed or downbeat, the entire universe exists within you. Live from the heart not the ego, that is the meaning of true living.