Nothing could be further from the truth (no pun intended).
The fact is that you cannot live your life in the real world on relativistic terms. Everyone believes in objective truth and objective morality and lives their lives accordingly. If someone claims not to believe in objective morality just steal his iPod and tell him that "your" morality allows it -- then watch his reaction. Or listen to the relativist (who loves to exalt the need to be tolerant and non-judgmental) respond to those someone who insists she is wrong about something and takes her to task on the issue. The fact is that relativists are the most intolerant, judgmental people you will ever meet.
They have to be, because no matter how strongly they deny objective reality, they have to live in the real world just like everyone else -- and no one can live in a relativistic world.
To deny the existence of absolute truth or morality is to deny the way the real world actually works. As my colleague Frank Turek puts it, when someone makes a relativistic claim, apply the claim to itself. Here's what it looks like:
They say: "There are no absolutes!" You respond: "Is that absolutely true?"
They say: "It may be true for you, but it's not for me." You respond: "Is that true for everybody, or just you?"
They say: "Doubt everything." You respond: "Should I doubt that, too?"
They say: "You shouldn't judge people!" You respond: "Then why are you judging me?"
Here's the thing about truth:
Contrary beliefs are possible, but contrary truths are not possible.
You can believe everything is true, but everything cannot be true.
Objective truth cannot be denied without being affirmed.
For the Christian, there is an equally pressing issue at stake because the denial of objective truth also runs up against the statements of Christ himself. Jesus Christ said that he came to "testify to the truth." He claimed that he was "THE way, THE truth, and THE life." He didn't say, "A" truth, he said "The" truth. There is no way to make those types of claims cohere with a relativistic view of truth. It just doesn't work. There certainly isn't any Biblical support for the concept of relative truth. The very idea is antithetical, not only to Christian doctrine, but to reality itself.
And nobody can live like that.