What could it mean to say that there is no absolute truth? It is absurd to assert this as a truth statement. What I see in people's web conversations is the idea that all truth claims are equally muddled by the claimant's perspective (or lack thereof.)
One person claims something to be true. Another claims the same something to be false. The relativist moderates by saying that from the first person's perspective the something is true and from the other person's perspective it is false. This is not too hard to swallow since people's opinions are certainly not infallible.
The problem comes when EVERYTHING is considered to be opinion and nothing is a fact. The relativist doesn't necessarily say there are no facts - he just claims that we don't have access to the facts. We only have our perception of the facts and our description of the facts are opinions.
It seems odd to me that modern science has contributed to the confusion. Science has claimed not only the physical universe but the metaphysical as its domain. Much of what science asserts as true truth about the universe is no more than a projection of naturalistic, materialistic and uniformitarian presuppositions. For example macro evolution has never been observed in nature, is not supported in the fossil record and is completely counter-intuitive in a world that is elegantly interwoven in overlapping systems that suggest design. But the secular scientists affirm that macro evolution is true truth 1) because it is the only explanation for how such a world could come to be that is thoroughly naturalistic and materialistic and 2) because most secular scientists believe it must be true and 3) because no matter how counter-intuitive it seems, some "scientist" somewhere has a "just so" story about how such systems might have progressed from one stage to another to form the incredibly complex organs, organisms and ecosystems we find today.
Science would like to be the arbiter of truth. Scientists consider themselves to be those who interact with the facts and who are unbiased in their testing and reporting of those facts. But since they refuse to acknowledge that their atheistic presuppositions shape their studies they cannot see that their application of the scientific method is fatally flawed so that their pronouncements are suspect to every thinking person.
Only an infinite personal God can be above the fray. He is the basic fact and every other factual reality comes from Him. He alone can speak with absolute authority about true truth > what exists, how it came to exist and why it exists > what is good and what is evil > what is life and how should we live? God knows, but is He saying?