Triangles are structurally superior to any other polygonal shape.

I watched as an ancient Buckminster Fuller waggled a rod-and-balljoint polygon around on my high school auditorium stage and popped out segment after segment until... the rectangle still wobbled.
But when he made a triangle... SOLID! (He actually leapt and shouted at this point. He was quite a spry ancient dude.)

I imagined structures made of triangles upon triangles, insanely huge fields of triangular shapes connecting and disconnecting over time like DNA and RNA dividing and replicating and folding over and over.
A social structure could be defined in such terms.

Sadly, over time, I've come to realize that triangles are horribly weak things when applied to human relationships.

Simply put, The Law of Triangles:

A likes B
B likes C
A hates the shit out of C
C doesn't think much of A, either.

Especially when A and C would rather break each others noses than break bread.
There will be times when you are A.
There will be times when you are B.
And there will be times when you are C.
(If you're D, it's best to just stay the fuck away from A, B and C until the dust settles and the ambulances drive off.)

How you recognize situations involving The Law of Triangles and how you deal with your role in them will determine your level of joy or misery in all relationships, simple and complex.

Especially when the C turns out to be you. Is it worth that much to you to be so detestable to A that it causes B discomfort to be around both you and A?