Get together

My friends were planning a get together for one of my friend’s birthday , the dilemma started when we were planning it. My friends were so disorganized  and did not have a plan, it was a huge mess.  So therefore I decided not to participate because I only knew that it would lead to a fight. Later after her birthday passed they  were questioning me and asking  why I did not come  to the get together, I just said I had plans. I got mad because they did not ask the other person why they did not come when they did not have any plans, when I did.  Why are my friends like this ?

https://en.wikipedia.org/wiki/Friends