Some are my cousins because they are my aunts & uncles' kids.
One is my cousin because her mom is almost related to my sister.
One is my cousin because when we were traveling together in our 20s, it was easier to explain than "just friends."
One is my cousin because I didn't want the guy I had a crush on to think he was my boyfriend.
Cousins are the sweet spot between family & friends, the best of both.