why do some people not understand

I want my online life and real life separate. Like this is a place for me to vent and i dont want people i know in real life to see my vents. Im only talking about this now because 2 guys started treating me like jackasses after i asked to change my nickname back to oscar in a discord server. i would have been fine if they just said no but like i said they started being jackasses about it. Like telling me to solve my own problem.