It's getting increasingly difficult to have anything resembling a rational discussion with people I disagree with in the era of "fake news". The problem of fake news (which at first referred only to stories that were basically completely fabricated, but now is applied to anything people don't think is fully true), is that there is no longer ANY agreement of a neutral arbiter of fact. It used to be that except for outliers in the far right and far left of intellectual discourse, there were certain media outlets that were accepted as Truth Seeking outlets that used a set of Journalistic Practices including trying hard to maintain objectivity and stick to facts, only using the opinions of others in stories and attributing, researching "both or all sides of a story" and to the extent they disagree, offer explanations to attempt to explain why they differ, and seeking corroboration for statements/facts from people with no known ties with the source.
Media outlets like the NY Times, Washington Post, NPR/PBS, and Network News (ABC, CBS, NBC) were widely considered "mainstream media." When they got something wrong, they tended to all get it wrong together--like the lead up to the Iraq War, in which the false or skewed information being fed to them by the Bush White House was carefully crafted to mislead them, and the number of stories that supported the Bush narrative got better and wider coverage, while stories questioning the intelligence became backpage stories.
The fact that the mainstream media occasionally makes mistakes does not make them fake news. It's similar to the scientific method, in which accepted science is not called FACT, it is called the PREVAILING THEORY, and other scientists are encouraged to challenge it and if they are able to prove any of it untrue through experimentation that can be replicated, then the theory is revised. In other words Journalism, like Science, seeks Truth, but understands that what is seen as FACT today, may change as new information comes to light.
But there have always been publications and media outlets and governments that instead of using the process of Journalism, use the tactics of PROPAGANDA to push a point of view and/or sell more advertising by getting more readers/viewers. National Enquirer, Fox News, and to some extent other cable news outlets, like MSNBC and even network news, now use many techniques like splashy, misleading headlines, opinion in the guise of news, or blatantly covering only one point of view.
Because of that, many people who spend time following the right wing outlets like Fox News, Breitbart, and radio opinionators Rush LImbaugh, etc. have been convinced that they can't trust any other media outlets but theirs (and that's the way they see those of us who basically trust mainstream media to fact check and follow journalistic practice). In response to this, many organizations, media based, non-profit org based, and university based, have started fact checking services: PolitiFact, Fact Check.org, Snopes, etc. This was supposed to be that final arbiter and they scrupulously cite their sources and explain all sides of stories. Unfortunately, since they often find the right wing bubble media stories to be false, none of their followers will accept them as neutral arbiters. Hence, I've found it's largely a waste of time to argue with people with points of view that depend on the right wing propaganda machine for information.