Sure is. The show takes elements from real-life incidents to create its storyline. However, there might be some fictional additions or alterations for dramatic effect.
Well, 'the real dirty john story' could potentially be a story about a John who has done some really bad things. Maybe he was involved in fraud, or had some immoral relationships. Without more context, it's hard to say exactly, but it generally implies that this John has a rather 'dirty' or unseemly history.
Since I don't know what the 'John Dirty Real Story' is, I can't really give you the details. It might be a story within a certain community, a family, or a specific event related to a John, but without more context, I'm at a loss.
As I don't know the actual story, I can't say what its significance is. It could be significant to the people directly involved in the story, perhaps teaching a lesson or being a memorable experience for them.
The real story of 'Dirty John' is centered around John Meehan and Debra Newell. John was a master manipulator. He entered Debra's life and slowly took over. He was able to convince her to trust him completely, even though there were signs that something was wrong. He used her money for his own vices, like his drug habit. The relationship deteriorated as Debra started to realize the truth. There were numerous incidents where John showed his true, menacing side, and it was a long and harrowing journey for Debra to break free from his hold.