That's fine no? I mean if you have nothing left to do until the event comes, just do not play until the event comes around. There are plenty of activities to keep you busy if you are into those things (i.e. pvp, shiny hunting, talking shit to people etc.), but if you are not just log in when there is something to do that you enjoy.
I don't know why you should expect any game to keep you entertained 24/7 365 days round. If you feel like you have done everything in the game you want to do, that's okay, and I hope you had fun doing so. Nothing wrong with requesting additonal things to do but there is more to do it's just that you are not particularly fond of those activities. And there is also nothing wrong with taking a break from a game and coming back when there is something to do again.