When I got my first job, I quickly became friends with one coworker. We were inseparable. He was kind, sympathetic, but only until 6 p.m. After that he would as if turn into a pumpkin — didn’t respond to messages, avoided meeting me.
6 months later, I found out that he was keeping an eye on me at our boss’s request. He was making sure that I worked normally and that I didn’t tell anyone any corporate secrets. In general, the coworker turned out to be not a friend, but the “eyes” of the boss.