The Relationship Triangle is a way to understand how people act within conflicts, and hopefully to avoid future conflicts. There are three potential roles people fit into: that of the persecutor, the victim, and the rescuer. People tend to assume at least one of these roles, often multiple ones in the same drama, shifting in and out. Example: Say someone is pressuring you to make a certain decision. They may think they are rescuing you from making a bad decision, yet you may perceive them as persecuting you and see yourself as a victim. Then a friend of yours may try to rescue you instead of you dealing with it yourself-etc. There is an article in Psychology Today that will describe it much more thoroughly and accurately for those of you interested.
One of the many reasons fairy tales have been around for so long and continue to resonate with us deeply is their ability to be a model for so many of our own issues. They can apply to whatever problems we're going through at different times in our lives, so we can turn to them time and time again for solace and hope that the problem will eventually be resolved.