*Disclaimer: There is no real point to this post. If you don't like Psychology, you probably won't want to read this.
Relationships are funny. They are constantly evolving and adapting because the people involved are. I was looking for an image that
would appropriately portray the area involved in a relationship, and this is the best I could find. There is Person Red and Person Blue, and they each exist independent of the other. A relationship is like the line between the two of them, blending to become Purple (it's not actually purple in this picture, but it should be). Based on experience, perceptions and personality differences, they each contribute to the relationship. They can maintain that Purple relationship while each also maintaining a unique identity, and role in the world. Some relationships have more overlap than others, I.E. they may or may not have the same friends, work, hobbies, religion, etc. And this is where is get's tricky: These two people can each have an independent relationship with a third Yellow person, and end up with an Orange relationship, and a Green relationship- which can be completely different from the Purple relationship Red and Blue share with each other. Make sense?
I think many people think that if they are witnessing a volatile relationship, they want to avoid those two people so as not to find themselves in a equally volatile relationship. This is not necessarily the case. Lets say the above Purple relationship was abusive. It is possible that Red and Blue bring out the worst in each other, and that their Orange and Green relationships with Yellow are healthy and not abusive. Obviously someone in an abusive relationship is a warning flag, but you know what I mean, right? It could be the case that those two personalities cannot mix in a productive and healthy way.
The point (I know: I said in the disclaimer that there wasn't really a point...I lied. I'm sorry.), I guess, is that relationships are complex, and are all unique. We cannot base our relationship expectations on the relationships of other people because our relationships are hugely influenced by our unique personalities.