who can say it's true that truth is relative?

I thought about truth today. Have you ever heard "truth is relative?" Even if I ignore how paradoxical it is, I can't get over how sad the thought is. Truth is constant and unchanging by definition. So, if truth is relative, it would mean there is no truth. Only what an individual decides is "true." Therefore, leaving us to our own devices. Fortunately, truth is truth, God is God, and we are not alone.

All is well.