u/Rhenus0

Hey guys, I am working in a coffee shop, 21M, and recently got a new coworker, 20F. She is a nice person and easy to be friends with, but recently her boyfriend came to visit her during our closing shift.
When he came in, she freaked out and told me she was going to take a break, then dragged the guy out. Later that night, I asked her if the guy was her boyfriend, and she said he was just a friend and ran away.After a couple of days, I heard that she has actually been in a relationship with her boyfriend for 3 years, and apparently everybody other than me already knew about it.Why would someone want to hide their relationship from a coworker?(For context we are not that close or something just coworkers)