4. What’s yours is theirs and vice versa.
I love it that my best friend and I can share clothes so we only have to buy stuff once
7. You know every intimate detail about each other — dietary restrictions, deepest secrets, middle names, etc.
10. You call each other’s parents by their first names.
16. You have more pictures together than most married couples.
17. You give each other cute notes and gifts when one of you is sick or having a bad week.